combo bug

I just noticed that combobox behaves strangely in gtk 2.2 when you do the following:
Click on the combo arrow, the dropdown list should appear. Now click anywhere but the arrow (e.g. application background). The dropdown list should disappear. Now move the mouse over the arrow. It renders as pressed while the mouse is over it. This is not reproduceable in Unix version.
P.S. I use a default gtk theme.