How to update a module to HEAD with CVS

I have a project with some modules which are backed up by CVS. The modules are loaded from a version tag.
I want to update one module to the HEAD "branch" to be able to commit changes.

I tried the CVS->Update Directory... functionality to do this. But I don't know what to select in the dialog.

I tried the following:

1. Use Version - Default -> updates to the currently loaded tag
2. Use Version - By tag (with 'HEAD' as tag) -> does not really work, only changes the loaded tag to HEAD but leaves the sticky tags
3. Use Version - By tag (with empty tag) -> does not work (shows error)

Can someone help me?

Thanks in advance!
Helge