fields on sstab disappear when form not checked out of sourcesafe

[c@lle]

I use several forms with sstab on it. It was working fine, but suddenly the information on the tabs is screwed up (i get on all my tabs the same fields).

This project is checked in with SourceSafe. When the forms are not editable (checked in in SourceSafe) the forms are screwed when you open them in Designmode.

If you check them out everything seems to be ok.

Does anybody knows what is happening???
Thanks