FF3 an AW2.5.2 - Combobox highlight border doesn't always hide

Using FF3 and AW 2.5.2 the rows in Combobox popup retains the blue border when mousover from bottom row to the top row. To reproduce start at the bottom most row in the Combobox using your Mouse pointer then move up to the top row. The row highlights correctly but the blue highlight border remains for some of the rows. If you go from top row back to bottom the borders disappear.

This looks like a Firefox bug. I'll see if I can find a workaround.