Windows 2003 DOS printing problem

We have set a W2k3 terminal server than connects to a W2k3 DC. DOS printing
redirection works fine using net use lpt1 \\server\printer but when a
different user issues the same command, the lpt1 of the previous user gets
redirected to the second user. Every time a user maps his printer, all
previous lpt1 redirected printers start printing on the last one that was
created.

Users are NOT part of any administrative group. Group policy is on the DC
and terminal server users are part of an OU on the DC.

Any hints