MyEclipse:IDE:Maven4MyEclipse 出异常：java.lang.NullPointerException

我装了 MyEclipse 9.1
创建 Maven web 工程时报错，如下：
 
!ENTRY org.eclipse.core.jobs 4 2 2012-01-27 20:54:06.750
!MESSAGE An internal error occurred during: "Creating project "StudyMavenWeb"".
!STACK 0
java.lang.NullPointerException
 at com.genuitec.eclipse.maven.project.MyEclipseProjectSupport.findWebRoot(MyEclipseProjectSupport.java:204)
 at com.genuitec.eclipse.maven.project.MyEclipseProjectSupport.configureWebProject(MyEclipseProjectSupport.java:71)
 at com.genuitec.eclipse.maven.project.MyEclipseProjectSupport.configure(MyEclipseProjectSupport.java:57)
 at org.maven.ide.eclipse.project.configurator.AbstractLifecycleMapping.configure(AbstractLifecycleMapping.java:57)
 at org.maven.ide.eclipse.internal.project.GenericLifecycleMapping.configure(GenericLifecycleMapping.java:48)
 at org.maven.ide.eclipse.internal.project.ProjectConfigurationManager.updateProjectConfiguration(ProjectConfigurationManager.java:332)
 at org.maven.ide.eclipse.internal.project.ProjectConfigurationManager.configureNewMavenProject(ProjectConfigurationManager.java:267)
 at org.maven.ide.eclipse.internal.project.ProjectConfigurationManager.enableMavenNature(ProjectConfigurationManager.java:343)
 at org.maven.ide.eclipse.internal.project.ProjectConfigurationManager.createSimpleProject(ProjectConfigurationManager.java:439)
 at org.maven.ide.eclipse.wizards.MavenProjectWizard$4.runInWorkspace(MavenProjectWizard.java:255)
 at org.eclipse.core.internal.resources.InternalWorkspaceJob.run(InternalWorkspaceJob.java:38)
 at org.eclipse.core.internal.jobs.Worker.run(Worker.java:54)