Hmm, you might want to check http://ophelia.cs.put.poznan.pl/xmlrep/, which is a project of Poznan University of Technology They made a wrapper around Xindice that seems to support locking.
When I read:
"Xindice has several bugs in version 1.0 - a patched binary release of Xindice (see Section 2.1)"
I start liking the GPL... :-(
-Vladimir
-- Vladimir R. Bossicard Apache Xindice - http://xml.apache.org/xindice
