An interesting thread on the jedit-users list about menu behavior. I read this message and then though to myself that the user must not be using a Mac. Lo and behold the reply to it was "Well you could get a Mac (HHOS)." Now for more info you should read this question to Tog, and Question 6 of Tog’s "A Quiz Designed to Give You Fitts".
The behavior of hierarchichal menus in the Mac OS is just another one of those ‘details’ I sometimes mention that make all the difference between it and other operating systems. This is why someone who has used a Mac for a long time has such a problem getting comfortable using Windows, but for someone who has used Windows and switches to a Mac, it’s something that might easily go by unnoticed. And honestly, that’s sort of how it should be, because as I said, it’s those subtle little things, the details, that make all the difference…
(Oh, and just in case you didn’t know HHOS is an acronym for "ha ha only serious")