Been seeing HeatBugs and Ant slow down to molasses-level speeds lately? 
  You're probably on MacOS X Leopard.  As part of releasing Java 1.6, 
Apple's been migrating from its Quartz-based Java2D graphics renderer to 
Sun's OpenGL-based renderer.  Problem is, Sun's renderer is much slower. 
  Even more of a problem: Apple has recently moved to do this by default 
for 1.5 as well, and on 1.5, Sun's renderer is _really_ pathetic.

I have made a few modifications to MASON so that Java is forced to use 
the Quartz renderer on Macs.  Things are now back to acceptable speeds. 
  These modifications are on CVS along with other recent changes.  If 
you would like a snapshot and can't do CVS, let me know.