GTK2 Menu button popup going the wrong way in duel monitor setup
 

Got an annoying problem I have a gtk menu tool button added to my toolbar with duel monitors one above the other and when I click the button to bring up the menulist when the app is on the bottom screen near the top the pop up tries to grow upwards but runs out of screen is there any way to force it to go down? can't seem to find an answer to this.

The attached pic shows what is happening