Error "Null Path" during VFS get virtual file

I have a jar file ,in which have "seam.properties" to load the seam components in it.
I put the jar file as a module.
But I got the following error when I start jboss.

java.lang.IllegalArgumentException: Null path
at org.jboss.vfs.VFS.getChild(VFS.java:187) [jboss-vfs-3.1.0.Final.jar:3.1.0.Final]
at org.jboss.vfs.VFS.getChild(VFS.java:173) [jboss-vfs-3.1.0.Final.jar:3.1.0.Final]
at org.jboss.vfs.VFS.getChild(VFS.java:154) [jboss-vfs-3.1.0.Final.jar:3.1.0.Final]
at org.jboss.seam.integration.jbossas.vfs.VFSScanner.getRoot(VFSScanner.java:36) [jboss-seam-int.jar:6.0.0.GA]

VFS.java:187 is following source.
return getChild(uri.getPath());

But in my case ,the uri pattern is create by org.jboss.modules.JarFileResourceLoader#getJarURI use the following method.
return new URI("jar", b.toString(), null);

It is the [scheme:]scheme-specific-partfragment pattern 's URI.it's path is null.
So when I change the VFS.java:187 to the following ,my problem is ok.IT's a bug?

public static VirtualFile getChild(URI uri) {
if(uri.getPath() != null)

{ return getChild(uri.getPath()); }

else

{ return getChild(uri.getSchemeSpecificPart()); }

}