pressing Alt and Spacebar is not opening the menu in Undecorated Dialog

following are the steps to reproduce the defect.
1.Create a Frame and make it visible.
2.Create "undecorated Dialog" with a button, now the focus is on Dialog.
3.press the keys ALT + Space bar.

expected result: menu should be displayed with move, size and close options.
Actual result: menu is not displayed.

1.This bug is reproducible only in windows it works in solaris, it occurs since JDK 1.5.0
please run the attached test to reproduce the defect.