samba - Mar 2004 - Samba 2.0.x and a "Mixed Mode" Server 2003 domain environment

I've recently upgraded our PDC to Server 2003, it's running in mixed
mode with a BDC running NT 4.0 (for now)

We're using samba 2.0.X for some legacy network shares, and a print
spool... 

I am encounting some issues on a couple computers where these samba
shares, upon first login work just fine, but after an unspecified period
of time (1 hour? 6 hours?) the shares become 'disconnected network
drives' to Windows clients, as well, windows cannot connect to the print
spool on this machine..

The client computers symptoms include wait times when browsing 'my
computer', excessive time waiting for print dialogs, and print jobs that
fail due to communication errors with the spool. Easiest way to 'fix'
the problem is to re-login..

Samba is configured to communicate to the Domain controllers for
authentication.

Are there any issues or experiences someone could share with me that
might point me in the right direction on where to resolve this? Thank
you,

- Steve Host