[cvsnt] linux client for windows based cvs server

[Munib]

Hi,
      I have a CVSNT server running 1.11.1.3(build62) in Windows 2000 PDC and I am using NT server based authentication for CVS. In windows we use WinCVS client. I want to access this server from Linux based clients running RedHat,FC2,Mandrake Linux OSs. Kindly clarify the following.
1. can I use CVS for linux or have I to use only CVSNT for linux in the client systems.
2. Is there any GUI client for linux OS.

     I have cvs-1.11.5-1mdk installed in a mandrake 9.1 linux system and if I try the following, I am getting the error as below.
(192.168.1.225 is the IP address of the Windows 2000 PDC running the CVSNT server)
 
[root at mail root]# CVSROOT=":pserver:munib:rmm123 at 192.168.1.225:/projects"
[root at mail root]# export CVSROOT
[root at mail root]# cvs checkout testmodule
Fatal error, aborting.
munib: no such user
    Kindly tell me where I am wrong.

Regards,
Munib