This error message may appear in some rare situations, when your time zone settings are not properly identified. To fix this, edit your eclipse.ini file and make sure it contains the -Duser.timezone definition.
Example: -Duser.timezone=Etc/GMT+1
Then change it manually to something else, ideally to value that can be retrieved from Oracle using this select:
SELECT * FROM V$TIMEZONE_NAMES
When you run Eclipse (3.5 or 3.6) on Linux, SWT components require XULRunner 1.8 or 1.9. However, newer Linux distributions come with XULRunner 2.0 that is related to Firefox 4. Unfortunately, SWT components do not run correctly in that environment and Toad Extension for Eclipse/Eclipse may crash.
The problem is not caused by Toad Extension for Eclipse. There are more possible solutions that can be found on the internet (not always working), one of them is installing the older supported XULRunner version. So far, we do not know about an "official" solution from the Eclipse or SWT.