I had been having horrific project load times (>25 minutes) on a single CPU Windows XP, 1 GB RAM system running Diana #8940 and java 1.6u10.
I disabled the 'Java Quick Start' from the 'Control panel' and my project now loads in about 10 minutes.
While this isn't ideal it is much better than before.
I didn't try any combinations of deleting caches, or closely time start times since I was trying to perform other work.
Personally the 'Java Quick Start' approach seems brains dead: continiously load the 'Most used' java libraries causing page faults (I had 40 Million in 1 day) just to keep 25 MB of libraries in memory.
I am sure if you have a Dual Core CPU and 4GB of RAM you might be able to afford the CPU cycles, so your results will vary.