windows not refreshing properly in compiz

I am using the interpid beta with all update run as of 9/10/08.

With compiz enabled sometimes window are not being repainted properly when the content changes, e.g. when i switch tabs in firefox the last page remains and as I move the mouse over the page certain parts those parts show up. It happens with all apps though - not just firefox , another example is in compiz setting manager, when i switch beetween different categories the button dont show up in the white are until i mouse over them or move the window.

When moving the window a repaint seems to be forced and the content shows up as expected. It seems like content is being cached and is only refreshes after some user event.