mandatory lock

[Jeeva Chelladhurai]

Hi,

I am trying to do an mandatory like using the a tag, thought the brach
tag exist, I get the following msg.

cvs admin -lBRANCH_5_10 test.cc
RCS file: /nfs/eagles/export/home/jeeva/mycvs/src/Attic/test.cc,v
cvs admin: /nfs/eagles/export/home/jeeva/mycvs/src/Attic/test.cc,v:
branch BRANCH_5_10 absent
cvs admin: cannot modify RCS file for `test.cc'

Am I doing some thing wrong? How do I do an Mandatory lock in cvs.

Thanks

Jeeva.