It is now possible to connect to a Windows machine running Logmein from Linux using a Java browser plugin…..unfortunately if you are using a 64-bit kernel on Ubuntu Karmic, then the java version from the Ubuntu repos is incompatible with the plugin.
To work around this, download https://secure.logmein.com/activex/logmein-client-1.0.387-1.tar.gz, and extract to ~/.mozilla/plugins/ then download and install nspluginwrapper from the repos (sudo apt-get install nspluginwrapper). Nspluginwrapper is a tool to create a layer of compatibility for non-native browser plugins.
You can then use nspluginwrapper by using:
sudo nspluginwrapper -i ~/.mozilla/plugins/libractrl.so
Restart firefox and navigate to the logmein website again and it should work…