A diff on two page revisions (e.g. http://confluence.atlassian.com/pages/diffpages.action?pageId=412&originalId=552) can result in the following system error being displayed in the browser:

Cause:
java.lang.ArithmeticException: / by zero

Stack Trace:
java.lang.ArithmeticException: / by zero
at com.atlassian.confluence.util.DiffUtils.diffLine(DiffUtils.java:310)
at com.atlassian.confluence.util.DiffUtils.printDeletedLines(DiffUtils.java:160)
at com.atlassian.confluence.util.DiffUtils.printChangedLines(DiffUtils.java:138)
at com.atlassian.confluence.util.DiffUtils.generateDiff(DiffUtils.java:97)
at com.atlassian.confluence.pages.actions.AbstractDiffPagesAction.execute(AbstractDiffPagesAction.java:33)
at com.opensymphony.xwork.DefaultActionInvocation.invoke(DefaultActionInvocation.java:173)
at com.opensymphony.xwork.interceptor.AroundInterceptor.intercept(AroundInterceptor.java:37)
at com.opensymphony.xwork.DefaultActionInvocation.invoke(DefaultActionInvocation.java:170)
at com.opensymphony.xwork.interceptor.DefaultWorkflowInterceptor.intercept(DefaultWorkflowInterceptor.java:58)
at com.atlassian.confluence.core.ConfluenceWorkflowInterceptor.intercept(ConfluenceWorkflowInterceptor.java:32)
at com.opensymphony.xwork.DefaultActionInvocation.invoke(DefaultActionInvocation.java:170)
at com.opensymphony.xwork.interceptor.AroundInterceptor.intercept(AroundInterceptor.java:37)
at com.atlassian.confluence.core.ConfluenceValidationInterceptor.intercept(ConfluenceValidationInterceptor.java:18)
at com.opensymphony.xwork.DefaultActionInvocation.invoke(DefaultActionInvocation.java:170)
at com.opensymphony.xwork.interceptor.AroundInterceptor.intercept(AroundInterceptor.java:37)
at com.opensymphony.xwork.DefaultActionInvocation.invoke(DefaultActionInvocation.java:170)
at com.atlassian.confluence.security.actions.PermissionCheckInterceptor.intercept(PermissionCheckInterceptor.java:40)
at com.opensymphony.xwork.DefaultActionInvocation.invoke(DefaultActionInvocation.java:170)
at com.opensymphony.xwork.interceptor.AroundInterceptor.intercept(AroundInterceptor.java:37)
at com.opensymphony.xwork.DefaultActionInvocation.invoke(DefaultActionInvocation.java:170)
at com.opensymphony.xwork.interceptor.AroundInterceptor.intercept(AroundInterceptor.java:37)
at com.opensymphony.xwork.DefaultActionInvocation.invoke(DefaultActionInvocation.java:170)
at com.opensymphony.xwork.interceptor.AroundInterceptor.intercept(AroundInterceptor.java:37)
at com.opensymphony.xwork.DefaultActionInvocation.invoke(DefaultActionInvocation.java:170)
at com.opensymphony.xwork.interceptor.AroundInterceptor.intercept(AroundInterceptor.java:37)
at com.opensymphony.xwork.DefaultActionInvocation.invoke(DefaultActionInvocation.java:170)
at com.opensymphony.xwork.DefaultActionProxy.execute(DefaultActionProxy.java:116)
at com.opensymphony.webwork.dispatcher.ServletDispatcher.serviceAction(ServletDispatcher.java:182)
at com.opensymphony.webwork.dispatcher.ServletDispatcher.service(ServletDispatcher.java:162)
at javax.servlet.http.HttpServlet.service(HttpServlet.java:103)
at com.caucho.server.http.FilterChainServlet.doFilter(FilterChainServlet.java:96)
at com.opensymphony.module.sitemesh.filter.PageFilter.parsePage(PageFilter.java:129)
at com.atlassian.confluence.util.profiling.ProfilingPageFilter.parsePage(ProfilingPageFilter.java:36)
at com.opensymphony.module.sitemesh.filter.PageFilter.doFilter(PageFilter.java:61)
at com.caucho.server.http.FilterChainFilter.doFilter(FilterChainFilter.java:88)
at com.atlassian.seraph.filter.SecurityFilter.doFilter(SecurityFilter.java:161)
at com.caucho.server.http.FilterChainFilter.doFilter(FilterChainFilter.java:88)
at com.atlassian.seraph.filter.LoginFilter.doFilter(LoginFilter.java:181)
at com.caucho.server.http.FilterChainFilter.doFilter(FilterChainFilter.java:88)
at com.atlassian.johnson.filters.JohnsonFilter.doFilter(JohnsonFilter.java:96)
at com.caucho.server.http.FilterChainFilter.doFilter(FilterChainFilter.java:88)
at org.springframework.orm.hibernate.support.OpenSessionInViewFilter.doFilterInternal(OpenSessionInViewFilter.java:83)
at com.atlassian.confluence.setup.SpringSessionInViewFilter.doFilterInternal(SpringSessionInViewFilter.java:32)
at org.springframework.web.filter.OncePerRequestFilter.doFilter(OncePerRequestFilter.java:39)
at com.caucho.server.http.FilterChainFilter.doFilter(FilterChainFilter.java:88)
at com.atlassian.util.profiling.filters.ProfilingFilter.doFilter(ProfilingFilter.java:132)
at com.caucho.server.http.FilterChainFilter.doFilter(FilterChainFilter.java:88)
at com.atlassian.core.filters.AbstractEncodingFilter.doFilter(AbstractEncodingFilter.java:38)
at com.caucho.server.http.FilterChainFilter.doFilter(FilterChainFilter.java:88)
at com.caucho.server.http.Invocation.service(Invocation.java:315)
at com.caucho.server.http.HttpRequest.handleRequest(HttpRequest.java:246)
at com.caucho.server.http.HttpRequest.handleConnection(HttpRequest.java:163)
at com.caucho.server.TcpConnection.run(TcpConnection.java:139)
at java.lang.Thread.run(Thread.java:534)