[cvsnt] Why is cvs update -A -r tag not possible?

[Tobias Schnakenberg]

Is this right: If I update my working directory by a static tag, there
is no way
to remove sticky tags (even not with the -A option). If I made changes
on my
local copy and want to commit it back to the repository, first I have to
create
a branch, commit on that and later merge back to the main trunk.
 
Why is cvs update -A -r <static_tag> not possible?