what's the matter on node search ?

[Yao Harrison]

Hi list:

code :
    public void searchVersion()throws RepositoryException{
        Workspace ws = session.getWorkspace();
        QueryManager qm = ws.getQueryManager();
        Query q =
qm.createQuery("/jcr:system/jcr:versionStorage//1.2",Query.XPATH);
        QueryResult qr = q.execute();
    }

error info:
javax.jcr.query.InvalidQueryException: Internal error: data is not a
RelationQueryNode

tree:
/root
|------jcr:system
   |-------jcr:versionStorage
         |---------ca
         |---------11
               |---------05
                     |-------------oe
                             |--------------11050exxxxxxx-xxxx-xxxxx
                                  |---------------jcr:rootVersion
                                  |---------------1.0
                                  |---------------1.1
                                  |---------------1.2
                                  |---------------1.3
|------NodeA
|------NodeB


How could this be ? any suggestions ?
Thanks for your ideas !

Harrison