REG: Popup Menu flickers badly on XToolkit

I have added a popup menu to a text area. When right clicking inside the text area, popup menu appears. When I navigate through all the menus in the popup menu, the popup menu flickers for every keyboard navigation.

This is reproducible on XAWT on Mustang-b55 but not reproducible on Mustang-b42 or earlier. Hence it is a regression introduced in some build between b42-b55. This is not reproducible with Motif/Win32. I reproduced it SolarisSparc10-JDS with b55-b59.

I have attached a sample test. Execute the sample test. You would see a frame with a text area, button and a menu. Click on the button. Menu will be removed from the menubar and added as a popup menu to the text area. Right click inside the text area. A popup menu will appear. Use the arrow keys and navigate through all the menus in the popup menu. You would notice that the popup menu flickers for every movement of arrow keys.