Hi Bob,
This force paste as text is a configuration option in FCKeditor. I enabled this feature on purpose because I was seeing a lot of invalid html being pasted into the forums when people would copy error messages or html fragments.
The only bug is in my implementation to make it do this in the forums, it seems to also do it in other features even if you are admin which was not my original intention so I need to review it and fix that.
Its definitely not a bug in FCKeditor, its a feature.
Best,
Joe