Filter: "Failed to Fetch Members: The call failed on the server; see server log for details"

[Cristian Veronesi]

Sorry, another problem. When I click on the icon beside the title
"Filter" I get this message: "Failed to Fetch Members: The call failed
on the server; see server log for details". The server log is la long
stacktrace that starts with:

2010-06-09 11:32:08,657 ERROR
[org.pentaho.pat.server.servlet.AbstractServlet] A RPC call resulted
in the following exception :
com.google.gwt.user.server.rpc.UnexpectedException: Service method
'public abstract java.util.List
org.pentaho.pat.rpc.IDiscovery.getAllLevelProperties(java.lang.String,java.lang.String,java.lang.String)
throws org.pentaho.pat.rpc.exceptions.RpcException' threw an
unexpected exception: java.lang.NullPointerException
at
com.google.gwt.user.server.rpc.RPC.encodeResponseForFailure(RPC.java:
360)
at
com.google.gwt.user.server.rpc.RPC.invokeAndEncodeResponse(RPC.java:
546)
at
com.google.gwt.user.server.rpc.RemoteServiceServlet.processCall(RemoteServiceServlet.java:
166)
at
com.google.gwt.user.server.rpc.RemoteServiceServlet.doPost(RemoteServiceServlet.java:
86)
at javax.servlet.http.HttpServlet.service(HttpServlet.java:
710)
at javax.servlet.http.HttpServlet.service(HttpServlet.java:
803)
....