I can't use it on MacOS X 10.1.4 (JRE 1.3.1). From the command line, it is really slow, and screen redraw is only partial or inexistent. The tabs don't respond to mouse clicks. If I enclose Phex in an executable, it works (until the next time I open Phex), but only if I change the interface theme (MacOS X to Metal, or the other way around). The menus work OK in all conditions.
I get a lot of big, long java error messages in the console, all mentioning the GUI, or the fact of "painting" it.
In the meantime I can't use 0.6.4 because 0.7 changed the format of my phexdownload.xml file.
Oh, and 2D acceleration (still in beta) does not work anymore. It worked perfectly with 0.6.4