Some programs like FrostWire will not work without Java being upgraded. To do this:

1. Use the Synaptic Package manager to add the repository: deb http://geekconnection.org xandros4 main. If you have no clue what that means read Installing software on the EEE - quick beginner's guide on the wiki.
2. After Synaptic has downloaded the files to update the repository; Scroll through the available items to locate xandros-sun-jre1.5; Mark it for installation; Click Apply.

The approximate size of this installation of Java is 30Mb and it is reported in this thread on the forum that after this version of Java was installed FrostWire works.

Based on information supplied by ph1me0w in the forum which he based on on instructions from david5t