[Samba] CUPS via SMB with per-user credentials?

[Kurt Granroth]

I have a multi-user Linux box in a mostly Windows NT/2000 shop.  The office
printer is available only via SMB (hosted by a Win2000 box) and access is
restricted to valid users in the local NT domain.  There is no "global" or
"print" user/password.

Everything mostly works.  I have a 'DeviceURI
smb://MYUSERNAME:MYPASSWORD@domain/printer' in /etc/cups/printers.conf. 
This allows all of the users on this Linux box to be able to print.

However, this isn't ideal for several reasons:
1. It's horribly unsecure as people with 'root' access on the Linux box
aren't the same as the NT admins.  Too many people can see my username and
password
2. All print jobs show up on my queue.  This can be pretty irritating when
the WinPopup messages keep popping up on my screen from somebody else's
print job.
3. Everybody has their own NT login credentials, so why not use them?

Unfortunately, I can't figure out any way to do this.  Basically, CUPS needs
to get the login credentials from someplace else other than the
printers.conf file.  It doesn't seem to honor or recognize the
$HOME/.credentials file that we use for share mounting.

I am more than willing to RTFM is such a FM exists.  Just point me in the
right direction!

Is this possible or am I out of luck?

Thank you,
Kurt Granroth
kurt-samba at granroth.org