>For what it's worth, did you try to look at the class construction of the pageframe using Class Browser? It may not be perfect, but Class Browser reveals a lot of problems for me.

Pageframe class doesn't have any code. Anyway, I found the problem code and fixed it. There was some code in two textboxes refresh. These textboxes were put on the form in order to execute thier refresh() method. I got rid of both of them and made form's method instead...