Unexpected TabPanel behavior

I wrote a procedure and triggered the procedure from a button on a form. Then I added a TabPanel to the same form and triggered the same procedure by clicking on one of the tabs in the TabPanel object. My procedure failed. I discovered there was some kind of a windowing problem going on. Here is what I have learned:

The following code:
OpenFile “RentCompare”
OpenSheet
Message Info(“WindowName”)
Stop

results in “RentCompare” when triggered from a button. However, the same code results in “RentCompare:SECRET” when triggered from a TabPanel on the same form. Is this correct behavior or am I misunderstanding something? Much thanks