LoC charts break when there's a commit dated more than 10 years in the future

2011-02-25 07:24:03,141 DEBUG [btpool0-22 ] fisheye.perf ProfilingServletFilter-logRequest - end request GET / sessionid=149rtlzscccud13z56nupzsnkr
2011-02-25 07:24:03,213 DEBUG [btpool0-22 ] fisheye.perf ProfilingServletFilter-logRequest - start request GET /fe/locChart.do?w=280&markEnd=0&username=ekoc&context=user-sparkline&outputtype=image&markStart=0&imageBackgroundColour=FFFFFF&h=32 sessionid=149rtlzscccud13z56nupzsnkr
2011-02-25 07:24:03,214 DEBUG [btpool0-11 ] fisheye.perf ProfilingServletFilter-logRequest - start request GET /fe/locChart.do?w=276&markEnd=0&username=ekoc&context=user&outputtype=image&markStart=0&imageBackgroundColour=FFFFFF&h=200 sessionid=149rtlzscccud13z56nupzsnkr
...
...
2011-02-25 07:24:03,235 INFO  [btpool0-22 ] fisheye.app TotalityFilter-logExceptionDetails - Exception "org.jfree.data.general.SeriesException: X-value already exists." (javax.servlet.ServletException) while processing "/fe/locChart.do" (Referer:"http://reviews:8060/")
javax.servlet.ServletException: org.jfree.data.general.SeriesException: X-value already exists.
	at com.opensymphony.webwork.dispatcher.DispatcherUtils.serviceAction(DispatcherUtils.java:284)
	at com.opensymphony.webwork.dispatcher.ServletDispatcher.service(ServletDispatcher.java:111)
	at javax.servlet.http.HttpServlet.service(HttpServlet.java:820)
	at org.mortbay.jetty.servlet.ServletHolder.handle(ServletHolder.java:511)
	at org.mortbay.jetty.servlet.ServletHandler$Chain.doFilter(ServletHandler.java:1217)
	at com.atlassian.plugin.servlet.filter.IteratingFilterChain.doFilter(IteratingFilterChain.java:46)
	at com.atlassian.plugin.servlet.filter.DelegatingPluginFilter$1.doFilter(DelegatingPluginFilter.java:66)
	at com.atlassian.applinks.core.rest.context.ContextFilter.doFilter(ContextFilter.java:25)
	at com.atlassian.plugin.servlet.filter.DelegatingPluginFilter.doFilter(DelegatingPluginFilter.java:74)
	at com.atlassian.plugin.servlet.filter.IteratingFilterChain.doFilter(IteratingFilterChain.java:42)
	at com.atlassian.plugin.servlet.filter.ServletFilterModuleContainerFilter.doFilter(ServletFilterModuleContainerFilter.java:77)
	at com.atlassian.plugin.servlet.filter.ServletFilterModuleContainerFilter.doFilter(ServletFilterModuleContainerFilter.java:63)
	at org.mortbay.jetty.servlet.ServletHandler$Chain.doFilter(ServletHandler.java:1209)