using xp credentials for ldap authentication

Scenario:

the windows xp user has autheticated againts a nt-domain (active diectory)
with credentials xpuser / xppassword. a java application running on this xp
box will access a server application located on unix. this server wants
authenticate the xpuser againts active directory.

Question:
is it possible to use the xppasword (cached in hash form in the registry)
for that authenticateion ? If not is there any other way to avoid requiring
to type the password (xppasword) by xpuser ?


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