NullPointerException while trying to change SVN URL

java.lang.NullPointerException
        at com.atlassian.bamboo.build.creation.RepositoryConfigHelper.prepareConfig(RepositoryConfigHelper.java:72)
        at com.atlassian.bamboo.ww2.actions.build.admin.config.ConfigureBuildRepository.validate(ConfigureBuildRepository.java:73)
        at com.opensymphony.xwork.interceptor.DefaultWorkflowInterceptor.doIntercept(DefaultWorkflowInterceptor.java:154)
        at com.atlassian.bamboo.ww2.interceptors.BambooWorkflowInterceptor.doIntercept(BambooWorkflowInterceptor.java:33)
        at com.opensymphony.xwork.interceptor.MethodFilterInterceptor.intercept(MethodFilterInterceptor.java:86)
        at com.opensymphony.xwork.DefaultActionInvocation.invoke(DefaultActionInvocation.java:190)
        at com.opensymphony.xwork.validator.ValidationInterceptor.doIntercept(ValidationInterceptor.java:116)
        at com.atlassian.bamboo.ww2.interceptors.BambooValidationInterceptor.doIntercept(BambooValidationInterceptor.java:33)
        at com.opensymphony.xwork.interceptor.MethodFilterInterceptor.intercept(MethodFilterInterceptor.java:86)
        at com.opensymphony.xwork.DefaultActionInvocation.invoke(DefaultActionInvocation.java:190)
        at com.atlassian.bamboo.ww2.interceptors.JSONValidationInterceptor.intercept(JSONValidationInterceptor.java:78)
        at com.opensymphony.xwork.DefaultActionInvocation.invoke(DefaultActionInvocation.java:190)
        at com.opensymphony.xwork.interceptor.AroundInterceptor.intercept(AroundInterceptor.java:31)
        at com.opensymphony.xwork.DefaultActionInvocation.invoke(DefaultActionInvocation.java:190)
        at com.opensymphony.xwork.interceptor.AroundInterceptor.intercept(AroundInterceptor.java:31)
        at com.opensymphony.xwork.DefaultActionInvocation.invoke(DefaultActionInvocation.java:190)
        at com.opensymphony.xwork.interceptor.AroundInterceptor.intercept(AroundInterceptor.java:31)
        at com.opensymphony.xwork.DefaultActionInvocation.invoke(DefaultActionInvocation.java:190)
        at com.opensymphony.webwork.interceptor.FileUploadInterceptor.intercept(FileUploadInterceptor.java:238)
        at com.opensymphony.xwork.DefaultActionInvocation.invoke(DefaultActionInvocation.java:190)
        at com.opensymphony.xwork.interceptor.AroundInterceptor.intercept(AroundInterceptor.java:31)
        at com.opensymphony.xwork.DefaultActionInvocation.invoke(DefaultActionInvocation.java:190)
        at com.opensymphony.xwork.interceptor.AroundInterceptor.intercept(AroundInterceptor.java:31)
        at com.opensymphony.xwork.DefaultActionInvocation.invoke(DefaultActionInvocation.java:190)
        at com.opensymphony.xwork.interceptor.AroundInterceptor.intercept(AroundInterceptor.java:31)
        at com.opensymphony.xwork.DefaultActionInvocation.invoke(DefaultActionInvocation.java:190)
        at com.opensymphony.xwork.interceptor.I18nInterceptor.intercept(I18nInterceptor.java:151)
        at com.opensymphony.xwork.DefaultActionInvocation.invoke(DefaultActionInvocation.java:190)
        at com.opensymphony.xwork.interceptor.AroundInterceptor.intercept(AroundInterceptor.java:31)
        at com.opensymphony.xwork.DefaultActionInvocation.invoke(DefaultActionInvocation.java:190)
        at com.atlassian.bamboo.security.acegi.intercept.web.WebworkSecurityInterceptor.intercept(WebworkSecurityInterceptor.java:55)
        at com.atlassian.bamboo.security.acegi.intercept.web.WebworkSecurityInterceptorProxy.intercept(WebworkSecurityInterceptorProxy.java:30)
        at com.opensymphony.xwork.DefaultActionInvocation.invoke(DefaultActionInvocation.java:190)
        at com.atlassian.bamboo.ww2.interceptors.PaginationAwareInterceptor.intercept(PaginationAwareInterceptor.java:84)
        at com.opensymphony.xwork.DefaultActionInvocation.invoke(DefaultActionInvocation.java:190)
        at com.atlassian.bamboo.ww2.interceptors.StatisticsAwareInterceptor.intercept(StatisticsAwareInterceptor.java:42)
        at com.opensymphony.xwork.DefaultActionInvocation.invoke(DefaultActionInvocation.java:190)
        at com.atlassian.bamboo.ww2.interceptors.ResultsListAwareInterceptor.intercept(ResultsListAwareInterceptor.java:45)
        at com.opensymphony.xwork.DefaultActionInvocation.invoke(DefaultActionInvocation.java:190)
        at com.atlassian.bamboo.ww2.interceptors.BuildResultsSummaryAwareInteceptor.intercept(BuildResultsSummaryAwareInteceptor.java:66)
        at com.opensymphony.xwork.DefaultActionInvocation.invoke(DefaultActionInvocation.java:190)
        at com.atlassian.bamboo.ww2.interceptors.ResultsSummaryAwareInteceptor.intercept(ResultsSummaryAwareInteceptor.java:67)
        at com.opensymphony.xwork.DefaultActionInvocation.invoke(DefaultActionInvocation.java:190)
        at com.atlassian.bamboo.ww2.interceptors.ChainAwareInterceptor.intercept(ChainAwareInterceptor.java:110)
        at com.opensymphony.xwork.DefaultActionInvocation.invoke(DefaultActionInvocation.java:190)
        at com.atlassian.bamboo.ww2.interceptors.PlanAwareInterceptor.intercept(PlanAwareInterceptor.java:71)
        at com.opensymphony.xwork.DefaultActionInvocation.invoke(DefaultActionInvocation.java:190)
        at com.opensymphony.xwork.interceptor.AroundInterceptor.intercept(AroundInterceptor.java:31)
        at com.opensymphony.xwork.DefaultActionInvocation.invoke(DefaultActionInvocation.java:190)
        at com.opensymphony.xwork.interceptor.AroundInterceptor.intercept(AroundInterceptor.java:31)
        at com.opensymphony.xwork.DefaultActionInvocation.invoke(DefaultActionInvocation.java:190)
        at com.opensymphony.xwork.interceptor.AroundInterceptor.intercept(AroundInterceptor.java:31)
        at com.opensymphony.xwork.DefaultActionInvocation.invoke(DefaultActionInvocation.java:190)
        at com.opensymphony.xwork.interceptor.ExceptionMappingInterceptor.intercept(ExceptionMappingInterceptor.java:186)
at com.opensymphony.xwork.DefaultActionInvocation.invoke(DefaultActionInvocation.java:190)
        at com.atlassian.bamboo.ww2.interceptors.BuildConfigurationInterceptor.intercept(BuildConfigurationInterceptor.java:54)
        at com.opensymphony.xwork.DefaultActionInvocation.invoke(DefaultActionInvocation.java:190)
        at com.atlassian.bamboo.ww2.interceptors.BuildConfigurationEditInterceptor.intercept(BuildConfigurationEditInterceptor.java:57)
        at com.opensymphony.xwork.DefaultActionInvocation.invoke(DefaultActionInvocation.java:190)
        at com.opensymphony.xwork.interceptor.AroundInterceptor.intercept(AroundInterceptor.java:31)
        at com.opensymphony.xwork.DefaultActionInvocation.invoke(DefaultActionInvocation.java:190)
        at com.opensymphony.xwork.DefaultActionProxy.execute(DefaultActionProxy.java:116)
        at com.opensymphony.webwork.dispatcher.DispatcherUtils.serviceAction(DispatcherUtils.java:274)
        at com.opensymphony.webwork.dispatcher.FilterDispatcher.doFilter(FilterDispatcher.java:202)
        at com.atlassian.bamboo.ww2.BambooFilterDispatcher.doFilter(BambooFilterDispatcher.java:30)
        at org.apache.catalina.core.ApplicationFilterChain.internalDoFilter(ApplicationFilterChain.java:215)
        at org.apache.catalina.core.ApplicationFilterChain.doFilter(ApplicationFilterChain.java:188)
        at com.atlassian.plugin.servlet.filter.IteratingFilterChain.doFilter(IteratingFilterChain.java:46)
        at com.atlassian.plugin.servlet.filter.ServletFilterModuleContainerFilter.doFilter(ServletFilterModuleContainerFilter.java:55)
        at com.atlassian.plugin.servlet.filter.ServletFilterModuleContainerFilter.doFilter(ServletFilterModuleContainerFilter.java:41)
        at org.apache.catalina.core.ApplicationFilterChain.internalDoFilter(ApplicationFilterChain.java:215)
        at org.apache.catalina.core.ApplicationFilterChain.doFilter(ApplicationFilterChain.java:188)
        at com.opensymphony.module.sitemesh.filter.PageFilter.parsePage(PageFilter.java:118)
        at com.opensymphony.module.sitemesh.filter.PageFilter.doFilter(PageFilter.java:52)
        at org.apache.catalina.core.ApplicationFilterChain.internalDoFilter(ApplicationFilterChain.java:215)
        at org.apache.catalina.core.ApplicationFilterChain.doFilter(ApplicationFilterChain.java:188)
        at com.opensymphony.webwork.dispatcher.ActionContextCleanUp.doFilter(ActionContextCleanUp.java:88)
        at org.apache.catalina.core.ApplicationFilterChain.internalDoFilter(ApplicationFilterChain.java:215)
        at org.apache.catalina.core.ApplicationFilterChain.doFilter(ApplicationFilterChain.java:188)
        at com.atlassian.plugin.servlet.filter.IteratingFilterChain.doFilter(IteratingFilterChain.java:46)
        at com.atlassian.plugin.servlet.filter.ServletFilterModuleContainerFilter.doFilter(ServletFilterModuleContainerFilter.java:55)
        at com.atlassian.plugin.servlet.filter.ServletFilterModuleContainerFilter.doFilter(ServletFilterModuleContainerFilter.java:41)
        at org.apache.catalina.core.ApplicationFilterChain.internalDoFilter(ApplicationFilterChain.java:215)
        at org.apache.catalina.core.ApplicationFilterChain.doFilter(ApplicationFilterChain.java:188)
        at com.atlassian.bamboo.filter.AccessLogFilter.doFilter(AccessLogFilter.java:66)
        at org.apache.catalina.core.ApplicationFilterChain.internalDoFilter(ApplicationFilterChain.java:215)
        at org.apache.catalina.core.ApplicationFilterChain.doFilter(ApplicationFilterChain.java:188)
        at org.acegisecurity.util.FilterChainProxy$VirtualFilterChain.doFilter(FilterChainProxy.java:265)
        at org.acegisecurity.providers.anonymous.AnonymousProcessingFilter.doFilter(AnonymousProcessingFilter.java:125)
        at org.acegisecurity.util.FilterChainProxy$VirtualFilterChain.doFilter(FilterChainProxy.java:275)
        at com.atlassian.bamboo.filter.SeraphLoginFilter.doFilter(SeraphLoginFilter.java:66)
        at org.acegisecurity.util.FilterChainProxy$VirtualFilterChain.doFilter(FilterChainProxy.java:275)
        at org.acegisecurity.util.FilterChainProxy.doFilter(FilterChainProxy.java:149)
        at org.acegisecurity.util.FilterToBeanProxy.doFilter(FilterToBeanProxy.java:98)
        at com.atlassian.bamboo.filter.BambooAcegiProxyFilter.doFilter(BambooAcegiProxyFilter.java:25)
        at org.apache.catalina.core.ApplicationFilterChain.internalDoFilter(ApplicationFilterChain.java:215)
        at org.apache.catalina.core.ApplicationFilterChain.doFilter(ApplicationFilterChain.java:188)
        at com.atlassian.bamboo.filter.LicenseFilter.doFilter(LicenseFilter.java:73)
        at com.atlassian.core.filters.AbstractHttpFilter.doFilter(AbstractHttpFilter.java:31)
        at org.apache.catalina.core.ApplicationFilterChain.internalDoFilter(ApplicationFilterChain.java:215)
        at org.apache.catalina.core.ApplicationFilterChain.doFilter(ApplicationFilterChain.java:188)
        at com.atlassian.johnson.filters.AbstractJohnsonFilter.doFilter(AbstractJohnsonFilter.java:72)
        at org.apache.catalina.core.ApplicationFilterChain.internalDoFilter(ApplicationFilterChain.java:215)
        at org.apache.catalina.core.ApplicationFilterChain.doFilter(ApplicationFilterChain.java:188)
        at com.atlassian.seraph.filter.SecurityFilter.doFilter(SecurityFilter.java:219)
        at org.apache.catalina.core.ApplicationFilterChain.internalDoFilter(ApplicationFilterChain.java:215)
        at org.apache.catalina.core.ApplicationFilterChain.doFilter(ApplicationFilterChain.java:188)
        at com.atlassian.seraph.filter.BaseLoginFilter.doFilter(BaseLoginFilter.java:140)
        at org.apache.catalina.core.ApplicationFilterChain.internalDoFilter(ApplicationFilterChain.java:215)
        at org.apache.catalina.core.ApplicationFilterChain.doFilter(ApplicationFilterChain.java:188)
        at com.atlassian.plugin.servlet.filter.IteratingFilterChain.doFilter(IteratingFilterChain.java:46)
        at com.atlassian.plugin.servlet.filter.DelegatingPluginFilter$1.doFilter(DelegatingPluginFilter.java:66)
        at com.atlassian.oauth.serviceprovider.internal.servlet.OAuthFilter.doFilter(OAuthFilter.java:69)
        at com.atlassian.plugin.servlet.filter.DelegatingPluginFilter.doFilter(DelegatingPluginFilter.java:74)
        at com.atlassian.plugin.servlet.filter.IteratingFilterChain.doFilter(IteratingFilterChain.java:42)
        at com.atlassian.plugin.servlet.filter.ServletFilterModuleContainerFilter.doFilter(ServletFilterModuleContainerFilter.java:55)
        at com.atlassian.plugin.servlet.filter.ServletFilterModuleContainerFilter.doFilter(ServletFilterModuleContainerFilter.java:41)
        at org.apache.catalina.core.ApplicationFilterChain.internalDoFilter(ApplicationFilterChain.java:215)
        at org.apache.catalina.core.ApplicationFilterChain.doFilter(ApplicationFilterChain.java:188)
        at org.springframework.orm.hibernate.support.OpenSessionInViewFilter.doFilterInternal(OpenSessionInViewFilter.java:170)
        at com.atlassian.bamboo.persistence.BambooSessionInViewFilter.doFilterInternal(BambooSessionInViewFilter.java:31)
        at org.springframework.web.filter.OncePerRequestFilter.doFilter(OncePerRequestFilter.java:75)
        at org.apache.catalina.core.ApplicationFilterChain.internalDoFilter(ApplicationFilterChain.java:215)
        at org.apache.catalina.core.ApplicationFilterChain.doFilter(ApplicationFilterChain.java:188)
        at com.planetj.servlet.filter.compression.CompressingFilter.handleDoFilter(CompressingFilter.java:203)
        at com.planetj.servlet.filter.compression.CompressingFilter.doFilter(CompressingFilter.java:193)
        at com.atlassian.bamboo.filter.CompressingFilter.doFilter(CompressingFilter.java:69)
        at org.apache.catalina.core.ApplicationFilterChain.internalDoFilter(ApplicationFilterChain.java:215)
        at org.apache.catalina.core.ApplicationFilterChain.doFilter(ApplicationFilterChain.java:188)
        at com.atlassian.bamboo.filter.RequestCacheThreadLocalFilter.doFilter(RequestCacheThreadLocalFilter.java:31)
        at org.apache.catalina.core.ApplicationFilterChain.internalDoFilter(ApplicationFilterChain.java:215)
        at org.apache.catalina.core.ApplicationFilterChain.doFilter(ApplicationFilterChain.java:188)
        at com.atlassian.plugin.servlet.filter.IteratingFilterChain.doFilter(IteratingFilterChain.java:46)
        at com.atlassian.plugin.servlet.filter.ServletFilterModuleContainerFilter.doFilter(ServletFilterModuleContainerFilter.java:55)
        at com.atlassian.plugin.servlet.filter.ServletFilterModuleContainerFilter.doFilter(ServletFilterModuleContainerFilter.java:41)
        at org.apache.catalina.core.ApplicationFilterChain.internalDoFilter(ApplicationFilterChain.java:215)
        at org.apache.catalina.core.ApplicationFilterChain.doFilter(ApplicationFilterChain.java:188)
        at org.springframework.web.filter.CharacterEncodingFilter.doFilterInternal(CharacterEncodingFilter.java:96)
        at org.springframework.web.filter.OncePerRequestFilter.doFilter(OncePerRequestFilter.java:75)
        at org.apache.catalina.core.ApplicationFilterChain.internalDoFilter(ApplicationFilterChain.java:215)
        at org.apache.catalina.core.ApplicationFilterChain.doFilter(ApplicationFilterChain.java:188)
        at org.apache.catalina.core.StandardWrapperValve.invoke(StandardWrapperValve.java:210)
        at org.apache.catalina.core.StandardContextValve.invoke(StandardContextValve.java:174)
        at org.apache.catalina.core.StandardHostValve.invoke(StandardHostValve.java:127)
        at org.apache.catalina.valves.ErrorReportValve.invoke(ErrorReportValve.java:117)
        at org.apache.catalina.core.StandardEngineValve.invoke(StandardEngineValve.java:108)
        at org.apache.catalina.connector.CoyoteAdapter.service(CoyoteAdapter.java:151)
        at org.apache.jk.server.JkCoyoteHandler.invoke(JkCoyoteHandler.java:200)
        at org.apache.jk.common.HandlerRequest.invoke(HandlerRequest.java:283)
        at org.apache.jk.common.ChannelSocket.invoke(ChannelSocket.java:773)
        at org.apache.jk.common.ChannelSocket.processConnection(ChannelSocket.java:703)
        at org.apache.jk.common.ChannelSocket$SocketConnection.runIt(ChannelSocket.java:895)
        at org.apache.tomcat.util.threads.ThreadPool$ControlRunnable.run(ThreadPool.java:685)
        at java.lang.Thread.run(Thread.java:619)