In case it helps anyone... it looks like the freeze has something to do with apple's accessibility options.
Can reproduce it by enabling VoiceOver or one of the other accessibility options and running this example
http://www.massapi.com/source/lwjgl-source-2.7.1/src/java/org/lwjgl/test/opengl/awt/AWTTest.java.htmlHappens with Java 7 & 8, if you take a thread dump you'll see something like sun.lwawt.macosx.CAccessibility.invokeAndWait(CAccessibility.java:75)
Delaying the creation of the canvas on the first paint call seems to help (if you can't just disable the accessibility options)
Thanks