.cvsignore is ignored

I don't understand exactly the problem. If the plug-in says that these
dll's should be checked in, I can suppose that these files were included in
the project and they are under source control. The purpose of a .cvsignore
file is to hide files that are not under source control. It should not
affect files that are already controlled. Generally both CVSSCC and WinCvs
are front-ends for cvs executable and should work equally with .cvsignore
file.

Possible solution of the problem depends on what you want to do with these
dll's. The following variants are possible.

1. Exclude these files from source control in the Visual Studio IDE using
'Exclude from Source Control' option in the 'Source Control' menu.
The files still remain under cvs control, so you can use WinCvs for update
or check in. But the IDE will not perform any source control operations
with these files.

2. Exclude these files from source control both in the IDE and WinCvs. Use
this way if the files were placed under source control accidentally by
mistake.

If you still have any questions, please describe your problem in more
details.