"Tag is not a branch"

[denebet]

Hello,

I got the following messages when trying to commit my dir :

cvs commit: Up-to-date check failed for `Makefile'
cvs commit: sticky tag `ot2-20080406' for file `ot2.kdevelop' is not a
branch
cvs commit: sticky tag `ot2-20080406' for file `ot2.kdevelop.pcs' is not a
branch
cvs commit: sticky tag `ot2-20080406' for file `ot2.kdevses' is not a branch
cvs commit: sticky tag `ot2-20080406' for file `src/Makefile' is not a
branch 
cvs commit: sticky tag `ot2-20080406' for file `src/ottreeview.h' is not a
branch
cvs [commit aborted]: correct above errors first!
[A quitté dans l'état 1]

A little googling shows that it is quite common but the fixes I tryied were
unsuccessfull (for eg suppres the tag ot2-20080406, try creating a branch).
Would someone be kind enough to give me  step by step instructions to
resolve this problem ?

TIA.

Alain