Something Went Wrong Error When Adding Link to Application Navigator

2014-11-17 14:58:09,783 ERROR [http-nio-8443-exec-6] jethomas @SD91SLx898x725x0 4d98rb 0:0:0:0:0:0:0:1 "POST /rest/custom-apps/1.0/customapps HTTP/1.1" c.a.p.r.c.e.j.ThrowableExceptionMapper Uncaught exception thrown by REST service: org/apache/commons/validator/routines/UrlValidator
java.lang.NoClassDefFoundError: org/apache/commons/validator/routines/UrlValidator
	at com.atlassian.plugins.custom_apps.rest.data.validation.UrlFieldValidator$Jira.isValid(UrlFieldValidator.java:211) ~[atlassian-nav-links-plugin-3.3.12_1413889954000.jar:na]
	at com.atlassian.plugins.custom_apps.DefaultCustomAppService.checkField(DefaultCustomAppService.java:379) ~[atlassian-nav-links-plugin-3.3.12_1413889954000.jar:na]
	at com.atlassian.plugins.custom_apps.DefaultCustomAppService.create(DefaultCustomAppService.java:278) ~[atlassian-nav-links-plugin-3.3.12_1413889954000.jar:na]
	at com.atlassian.plugins.custom_apps.rest.CustomAppsRestResource.create(CustomAppsRestResource.java:183) ~[atlassian-nav-links-plugin-3.3.12_1413889954000.jar:na]
	at com.atlassian.applinks.core.rest.context.ContextFilter.doFilter(ContextFilter.java:25) [applinks-plugin-4.3.0_1413889972000.jar:na]
	at com.atlassian.stash.internal.spring.security.StashAuthenticationFilter.doFilter(StashAuthenticationFilter.java:86) [StashAuthenticationFilter.class:na]
	at com.atlassian.stash.internal.web.auth.BeforeLoginPluginAuthenticationFilter.doInsideSpringSecurityChain(BeforeLoginPluginAuthenticationFilter.java:111) [BeforeLoginPluginAuthenticationFilter.class:na]
	at com.atlassian.stash.internal.web.auth.BeforeLoginPluginAuthenticationFilter.doFilter(BeforeLoginPluginAuthenticationFilter.java:77) [BeforeLoginPluginAuthenticationFilter.class:na]
	at com.atlassian.security.auth.trustedapps.filter.TrustedApplicationsFilter.doFilter(TrustedApplicationsFilter.java:100) [TrustedApplicationsFilter.class:na]
	at com.atlassian.oauth.serviceprovider.internal.servlet.OAuthFilter.doFilter(OAuthFilter.java:69) [atlassian-oauth-service-provider-plugin-1.9.2_1413889972000.jar:na]
	at com.atlassian.analytics.client.filter.DefaultAnalyticsFilter.doFilter(DefaultAnalyticsFilter.java:33) [analytics-client-3.48_1413889974000.jar:na]
	at com.atlassian.core.filters.AbstractHttpFilter.doFilter(AbstractHttpFilter.java:31) [AbstractHttpFilter.class:na]
	at com.atlassian.stash.internal.web.auth.BeforeLoginPluginAuthenticationFilter.doBeforeBeforeLoginFilters(BeforeLoginPluginAuthenticationFilter.java:89) [BeforeLoginPluginAuthenticationFilter.class:na]
	at com.atlassian.stash.internal.web.auth.BeforeLoginPluginAuthenticationFilter.doFilter(BeforeLoginPluginAuthenticationFilter.java:75) [BeforeLoginPluginAuthenticationFilter.class:na]
	at com.atlassian.stash.internal.request.DefaultRequestManager.doAsRequest(DefaultRequestManager.java:82) [DefaultRequestManager.class:na]
	at com.hazelcast.web.WebFilter.doFilter(WebFilter.java:463) [WebFilter.class:3.3.2-atlassian-3]
	at java.util.concurrent.ThreadPoolExecutor.runWorker(ThreadPoolExecutor.java:1145) [na:1.7.0_55]
	at java.lang.Thread.run(Thread.java:745) [na:1.7.0_55]
	... 199 frames trimmed
Caused by: java.lang.ClassNotFoundException: org.apache.commons.validator.routines.UrlValidator not found by com.atlassian.plugins.atlassian-nav-links-plugin [32]
	at org.apache.felix.framework.ModuleImpl.findClassOrResourceByDelegation(ModuleImpl.java:812) ~[ModuleImpl.class:na]
	... 19 common frames omitted