So you updated to Firefox 1.5 (why werent you running RC3?) and now a ton of your extentions do not work.. Here is a quick fix to force them to work. Remember this is just a fix, make sure to update them as soon as you can.

1. enter about:config into your location bar. This will show you a list of Firefox internal preferences.
2. Right-click on the list, select New > String
3. Enter “app.extensions.version” (without quotes) for the preference name.
4. Then, enter “1.0” (without quotes) as the value for app.extensions.version.
5. Restart Firefox 1.5, then enable those disabled Firefox extensions.
6. Restart Firefox 1.5 again to active the extensions. Done.