There has been certain issues with the recent updates of Firefox in Ubuntu 8.10. After installing all the recent updates in Ubuntu intrepid ibex, Firefox may start showing up some errors while trying to run the same. The most common error is the one which Firefox simply fails to start with an error message "Could not find compatible GRE between version 1.9b3 and 1.9b3".

This issue can be solved with a simple workaround. Take a look on How to solve the issue with Firefox caused while updating Ubuntu 8.10