cvs history with -r

[Murugaiyan, Natarajan [IT]]

I want to get a report which lists all files and revisions that were
committed 
on a branch since the branch was branched.

The cvs command I am using is
        cvs history -c -p btec -a -r S8PHASE1

This command lists revisions committed on branch S8PHASE1 on module btec,
but also lists revisions committed on the trunk.

Is something wrong with my command or is this a CVS problem?

I am using cvs 1.10 on Solaris 5.5.1. 

Thanks,

Natarajan Murugaiyan(Ravi)