Sticky tag does not prevent from removing files

[vdeconinck]

I am new to cvs "advanced" features, so maybe this message will seem 
completely odd to cvs gurus... sorry in advance if it's the case.

Here's the problem : while experiencing with branches, I came across 
the following situation :

I had a release tagged "REL-1", from which I wanted to branch to 
implement a few fixes, independently from the main trunk, so I did a :

cvs rtag -r REL1 -b REL1-FIX foo
cvs checkout -r REL1-FIX foo

I changed a few files, committed the changes then tagged the new 
version with

cvs tag REL1-FIX1 foo

... and exported that fixed version to the production directory. 
Nothing very special until now.

A few weeks later, I wanted to fix another issue, by simply removing
a 
file. So I checked out once again the files to an empty dir, but as I 
am (was) not an expert, I checked out the revision REL1-FIX1 instead 
of the branch REL1-FIX (note that if I'd been an advanced user, it 
could have been a typo). So here's what I typed :

cvs checkout -r REL1-FIX1 foo
cd foo
rm menu.html
cvs remove menu.html
cvs commit -m "Unused"

... and it worked ! CVS allowed me to commit even though I had a 
revision checked out, not a branch. Not even a warning... Worse, it 
took me a long time to realize something abnormal had happened, 
because I went on tagging that version : 

cd ..
cvs tag REL1-FIX2

... and then exporting from that tag REL1-FIX2 to the release dir, 
without any problem.

But the problem surfaced a few weeks later, when I wanted to
implement 
a third fix (Yes, I know, it's a pity to leave so many bugs in
release 
versions :-)), because I made a :

cvs checkout -r REL1-FIX foo

... and my menu.html was back to life, though I had erased it 
before...


So, is that a bug in CVS that allowed me to commit the removal or am
I 
missing something important with tags and branches ?

Any help/tip/comment is greatly appreciated

Vincent.