This happens with 2008v1 with no hotfixes applied. 

The scenario is that we had a WebTab control with the option set to scroll tabs if there are too many to fit along the top. The problem is that if you have any hidden tabs and you scroll right and then left again the hidden tabs reappear.

Has this been fixed in a newer release or hotfix? 

I have worked around it elsewhere be actually removing the tab I wish to hide from the collection but this isn't possible in one particular case (the hidimng and showing needs to be dynamic).