Soln for the exception - Specified VM install not found: type Standard VM, name java-6-openjdk, on building a project in Eclipse

On trying to build a project in Eclipse, a dialogue appears, showing the exception - "Specified VM install not found: type Standard VM, name java-6-openjdk" .

The solution is :
Delete the "[proj_name].launch" file in the location [workspace]/.metadata/.plugins/org.eclipse.debug.core/.launches

Os: Ubuntu 10
Eclipse : Indigo