get_md4pw was called with 2 params, one never used. mach_name and

get_md4pw was called with 2 params, one never used. mach_name and
mach_acct where mixed, the machine account wasn't correctly converted to
lower case.

srv_samr.c: added checks around Unix password changing. If it's a trust
account, don't change the unix password. That's the reason why people
having unix password sync=yes coudn't join a samba domain for a W2K box.

changed also the string_sub function in create_unix_account() to NOT strip
the ending $ on trust account.

For the security picky people, Jeremy is already aware :-)

	J.F.