You're experiencing the well-documented Window Manager bug. [Window Manager claims 60-90% of the CPU making it impossible to get any real work done.] As far as I know it's caused by LimeWire, not Java.

There's a simple work-around: Hide LimeWire before launching any other applications, and Hide each application before flip/flopping to LimeWire.

The LimeWire team has been conspicuously absent from this forum for several weeks now so we don't know how they're progressing on this bug or any of the other serious problems with 2.8.5.

Janet