U.S. Tech Blog ...

For starters, Running Eclipse IDE under Ubuntu would be a major hedache. You may encounter unusual number of errors including at Start-up , when running plugins , software updating , etc. Though the reason cannot be exactly pointed out , several issues standout among the rest ..First and foremost is the Eclipse SWT (Standard Widget ToolKit). Though a standard java lib ,SWT depends a lot on native platform features in order to provide nicer, richer graphical interface than AWT or Swing .

Therefore SWT library needs to be installed (if not provided ) for each platform you are running in but still may encounter errors (ie:-XPCOM Error , Widert Disposed too early, etc) due to dependencies on web browser ,etc. Eclipse Runtime GCJ would be another reason behind many issues including when running plugins, software updates, java debugging , etc. GCJ is the java compiler + runtime provided by GCC (GCJ v1.5) , which is actually an open-source implementation of java kernel provided with ubuntu , which unfortunately Eclipse picks up as it's default JRE for most Linux platforms.GCJ is not properly tested and not a intended Runtime expected by Eclipse Developers hence would be the origin for a lot of in-compatibilities.

Several work-arounds generally solve all these issues ,

• set Eclipse java virtual machine to java 1.5 0r 1.6 provided by SUN . This can be set in command line using ./eclipse -vm /${path to JDK Home}/bin/java or in eclipse.ini file specifying
  -vm
  /${path to JDK Home}/bin/java
  

• if a Startup problem is there try updating Ubuntu or install latest xulrunner and XPCOM (sudo apt-get install xulrunner) packages for ubuntu and append to eclipse.ini
  -Dorg.eclipse.swt.browser.XULRunnerPath=/usr/lib/xulrunner/xulrunner