Mac OS X 10.7.3 macmini4,1
Run a regression test closed/java/awt/Frame/PackTwiceTest/PackTwiceTest.
It doesn't set any sizes to a Frame and added there TextField but sets to the TextField first, a short text, then, a long one, calling pack() in between. Twice.
As a result, on Apple JDK 6 the Frame is of the first text size; on 7u4 b14 it has minimal possible size (just enough to show system buttons).