Possible bug when cvs checking out changelogs using a tag
That certainly cannot work with Hudson as it is written. I don't really follow why you would want this, actually; a tag is a static snapshot.
Surely you don't go changing the Hudson project configuration every time you want to do a build, to point it to a new tag?
No not at all. What we do is move the tags in cvs such that they point at the revision of the files that we would like for a stage build. In this way, the tags are not static snapshots but rather dynamic snapshots. Once we are satisfied with the STAGE build, we can replace the snapshot tag with a branch tag and call that our release. Incidentally, there are two other non-static tags in cvs that are always available to the client: HEAD and BASE.
It may not make much sense to you if your build is not done this way but our group has been doing it like this for several years and it has served us relatively well. It allows us to check work in progress into cvs and yet exclude it from test and stage builds if it is necessary to hold a feature back a few releases.