Kubuntu Java And Eclipse

I have 3gb ram and p4 2.6 cpu and 8400gs nvidia video card but I was still having gui freezing eclipse problems. in this morning I started digging talk with my friends and read forums about the performance problem. now I am freely telling you if you have eclipse which works really really slow. you need to install sun java. not gij or blacksmart or anything. sun works well and eclipse gui does not freeze anymore.