java problems

Hi here, need some help here.

I using XP OS, whenever i use IE6 to access java based websites (eg chatrooms). I received a prompt saying i dun have JVM installed and ask me d/l the plugin, however it still did not work after i installed the plugin. I also tried to d/l and install the related software in sun microsystem website but also dun work. Reinstalling the IE also failed to solved the problem. Can any1 help? Thanks.

note: in the IE's tools->internet options , under advance tab, i did not have the option for 'microsoft VM' where all the java related checkboxs are located(i dun have ANY checkboxs related to java). even after reinstalling the ie or the procedures describled above.

Thanks Again