Wayne Meissner, who works on gstreamer-java and JNA, asked me if JNA moving to Java 1.5 would cause problems for FMJ.
I personally find it limiting to always use 1.4, and although most of FMJ will compile/run without 1.5, there are a few corners which still require it.
In particular, lti-civil (used for video capture) and ffmpeg-java (used for wrapping ffmpeg) are using 1.5. Certainly their source code could be changed to remove generics and such if it were absolutely needed. However, I find that once you start using generics and see how it improves the code readability and quality, it is hard to go back.
I have told Wayne that I don't mind if JNA requires 1.5, but I thought I should solicit broader opinions on this, both from the FMJ and the SC teams.
I seem to recall that SC uses 1.4 as its standard, but I don't have any real info on that.