Cause : DISPLAY property variable is not set.
The issue is related to core Eclipse(3.x) launcher code bug, the TIBCO/BE Studio code never gets invoked at this point of time. Here is the Eclipse bug for your reference. https://bugs.eclipse.org/bugs/show_bug.cgi?id=314849
The bug is fixed in Eclipse Juno M2 (4.0), so when migrating BE to Eclipse 4.x, the issue will be resolved.