Input type date problem

Hello.
I'm add to my issues attribute with input type date, and not set is as
required. But if i'm not set date issue not added and scarab print error:

If the stack trace below has at the top a mention
of "ResourceNotFoundException", that means that a template could not be
found (404) and is probably the result of a broken link.

If the stack trace has something else, please enter a copy of the stack
trace *and an explanation of what you did to cause it* to the
Issue Tracking System <http://www.solitone.org/scarab/issues/> for analysis.
If you are a developer and think you know what the problem is,
feel free to send in a patch to fix the problem.

  org.apache.turbine.TurbineException: java.lang.NullPointerException
	at org.apache.turbine.pipeline.DefaultActionValve.invoke(DefaultActionValve.java:104)
	at org.apache.turbine.pipeline.TurbinePipeline.invokeNext(TurbinePipeline.java:231)
	at org.apache.turbine.pipeline.DefaultACLCreationValve.invoke(DefaultACLCreationValve.java:127)
	at org.apache.turbine.pipeline.TurbinePipeline.invokeNext(TurbinePipeline.java:231)
	at org.tigris.scarab.pipeline.SetLocaleValve.invoke(SetLocaleValve.java:112)
	at org.apache.turbine.pipeline.TurbinePipeline.invokeNext(TurbinePipeline.java:231)
	at org.tigris.scarab.pipeline.FreshenUserValve.invoke(FreshenUserValve.java:189)
	at org.apache.turbine.pipeline.TurbinePipeline.invokeNext(TurbinePipeline.java:231)
	at org.apache.turbine.pipeline.DefaultSessionValidationValve.invoke(DefaultSessionValidationValve.java:131)
	at org.apache.turbine.pipeline.TurbinePipeline.invokeNext(TurbinePipeline.java:231)
	at org.apache.turbine.pipeline.DefaultLoginValve.invoke(DefaultLoginValve.java:109)
	at org.apache.turbine.pipeline.TurbinePipeline.invokeNext(TurbinePipeline.java:231)
	at org.tigris.scarab.pipeline.AnonymousLoginValve.invoke(AnonymousLoginValve.java:62)
	at org.apache.turbine.pipeline.TurbinePipeline.invokeNext(TurbinePipeline.java:231)
	at org.tigris.scarab.pipeline.NTLMLoginValve.invoke(NTLMLoginValve.java:78)
	at org.apache.turbine.pipeline.TurbinePipeline.invokeNext(TurbinePipeline.java:231)
	at org.apache.turbine.pipeline.DefaultSessionTimeoutValve.invoke(DefaultSessionTimeoutValve.java:121)
	at org.apache.turbine.pipeline.TurbinePipeline.invokeNext(TurbinePipeline.java:231)
	at org.tigris.scarab.pipeline.DetermineTargetValve.invoke(DetermineTargetValve.java:138)
	at org.apache.turbine.pipeline.TurbinePipeline.invokeNext(TurbinePipeline.java:231)
	at org.apache.turbine.pipeline.DetermineActionValve.invoke(DetermineActionValve.java:107)
	at org.apache.turbine.pipeline.TurbinePipeline.invokeNext(TurbinePipeline.java:231)
	at org.tigris.scarab.pipeline.SetInfoMessageValve.invoke(SetInfoMessageValve.java:85)
	at org.apache.turbine.pipeline.TurbinePipeline.invokeNext(TurbinePipeline.java:231)
	at org.tigris.scarab.pipeline.ResetCacheValve.invoke(ResetCacheValve.java:77)
	at org.apache.turbine.pipeline.TurbinePipeline.invokeNext(TurbinePipeline.java:231)
	at org.tigris.scarab.pipeline.DetermineCharsetValve.invoke(DetermineCharsetValve.java:103)
	at org.apache.turbine.pipeline.TurbinePipeline.invokeNext(TurbinePipeline.java:231)
	at org.tigris.scarab.pipeline.TimingInfoValve.invoke(TimingInfoValve.java:131)
	at org.apache.turbine.pipeline.TurbinePipeline.invokeNext(TurbinePipeline.java:231)
	at org.apache.turbine.pipeline.TurbinePipeline.invoke(TurbinePipeline.java:213)
	at org.apache.turbine.Turbine.doGet(Turbine.java:298)
	at org.apache.turbine.Turbine.doPost(Turbine.java:343)
	at javax.servlet.http.HttpServlet.service(Unknown Source)
	at javax.servlet.http.HttpServlet.service(Unknown Source)
	at org.apache.catalina.core.ApplicationFilterChain.internalDoFilter(Unknown
Source)
	at org.apache.catalina.core.ApplicationFilterChain.doFilter(Unknown Source)
	at org.apache.catalina.core.StandardWrapperValve.invoke(Unknown Source)
	at org.apache.catalina.core.StandardContextValve.invoke(Unknown Source)
	at org.apache.catalina.authenticator.AuthenticatorBase.invoke(Unknown Source)
	at org.apache.catalina.core.StandardHostValve.invoke(Unknown Source)
	at org.apache.catalina.valves.ErrorReportValve.invoke(Unknown Source)
	at org.apache.catalina.core.StandardEngineValve.invoke(Unknown Source)
	at org.apache.catalina.connector.CoyoteAdapter.service(Unknown Source)
	at org.apache.jk.server.JkCoyoteHandler.invoke(Unknown Source)
	at org.apache.jk.common.HandlerRequest.invoke(Unknown Source)
	at org.apache.jk.common.ChannelSocket.invoke(Unknown Source)
	at org.apache.jk.common.ChannelSocket.processConnection(Unknown Source)
	at org.apache.jk.common.ChannelSocket$SocketConnection.runIt(Unknown Source)
	at org.apache.tomcat.util.threads.ThreadPool$ControlRunnable.run(Unknown
Source)
	at java.lang.Thread.run(Thread.java:619)
Caused by: java.lang.NullPointerException
	at java.text.SimpleDateFormat.parse(SimpleDateFormat.java:1215)
	at java.text.DateFormat.parse(DateFormat.java:335)
	at org.tigris.scarab.attribute.DateAttribute.internalDateFormat(DateAttribute.java:105)
	at org.tigris.scarab.attribute.DateAttribute.convertDateAttributes(DateAttribute.java:138)
	at org.tigris.scarab.actions.ReportIssue.enterIssue(ReportIssue.java:450)
	at org.tigris.scarab.actions.ReportIssue.doEnterissue(ReportIssue.java:430)
	at sun.reflect.NativeMethodAccessorImpl.invoke0(Native Method)
	at sun.reflect.NativeMethodAccessorImpl.invoke(NativeMethodAccessorImpl.java:39)
	at sun.reflect.DelegatingMethodAccessorImpl.invoke(DelegatingMethodAccessorImpl.java:25)
	at java.lang.reflect.Method.invoke(Method.java:597)
	at org.apache.turbine.modules.actions.TemplateAction.executeEvents(TemplateAction.java:160)
	at org.apache.turbine.modules.ActionEvent.perform(ActionEvent.java:144)
	at org.apache.turbine.modules.actions.TemplateSecureAction.perform(TemplateSecureAction.java:90)
	at org.apache.turbine.modules.ActionEvent.execute(ActionEvent.java:179)
	at org.apache.turbine.pipeline.DefaultActionValve.executeAction(DefaultActionValve.java:139)
	at org.apache.turbine.pipeline.DefaultActionValve.invoke(DefaultActionValve.java:99)
	... 50 more

 How fix this trouble?