Eclipse SDK start-up

Install sun-java6-jdk, then select it as your default java system.

Use Sun's Java instead of the open source GIJ (GNU Java bytecode interpreter) you need to set it as default. To list installed JVMs:

update-java-alternatives -l

sudo /etc/eclipse/java_home

Move:

/usr/lib/jvm/java-6-sun
/usr/lib/jvm/java-1.5.0-sun

To the top of the list.

Source: http://www.radrails.org/trac/ticket/6559