Can't Check in

We have migrated to a new network environment with a new cvs server.

I can check out, but now I cant check-in due to unrecognized cvs option --c
(see attachment 1). I am using 2.x series plugin with 1.x series server
(see attachment 2). Is this the reason for my problem?

Is there a workround? If not...

Does my license allow mw to try 1.x series plugin? - I have an important
demo coming up, and my credit card is blocked - so for practical reasons I
would like to check with you first.

Thankyou.