Appreciate the help given on this forum. Here is a fix note in case anyone else ever experiences the 'out of memory...permgen' error with their version of Java. I got it with build 1.5.0_02-b09, but I hear they have fixed this since.
Anyway, the fix was for me to add this to the batch file I have starting the pandora mp3 server:
-XX:MaxPermSize=512m
Hope this helps someone.
PS. I was using MusicMatch to 'SuperTag' all my MP3's. Now I find that I have a bunch of MP3's that were incorrectly renamed/tagged. Can anyone recommend a good program to scan all my mp3's and correctly name/tag them?