[Samba] How to Change samba's PW from XP

[jayb]

I could really use a quick yes/no answer here. If answer yes
a pointer to a Howto. 
 
I have a samba based file server running in workgroup mode with
security = user 
 
XP User authentication is managed by a separate LDAP server.
 
Is there a way from within XP such as  command utility, anything, I could use to
update the samba server's password?
 
RIght now, it a manual excerise to update the samba server password everytime the
user changes his/her password.
 
I see this question asked a lot but I just can't seem to fine an answer.
 
When working as a PDC, what mechanism is used to update the user's password then?
 
 
thanks
 
jay