Nerd Alert Ultra-specific nerdery.

At a command prompt run:

sudo apt-get install ia32-sun-java6-bin

... or get it from Synaptic.

Download a 32-bit version of Eclipse from: eclipse.org. Extract the package to your home directory.

Right click on the Gnome panel and select "Add to Panel..."

Select "Custom Application Launcher" and click "Add"
Name: Eclipse IDE
Command: /home/qk/eclipse/eclipse -vm /usr/lib/jvm/ia32-java-6-sun/bin/java
Comment:qk is the coolest :)
(You can also set the icon by clicking on the default icon and navigating to your eclipse install directory. Replace qk with your username and/or eclipse with where you put eclipse.)
Click "OK"

Click the Eclipse launcher and you should be all set.