Still happily living on jEdit for most of my scripting. I haven’t found an actionscript 3 edit mode, so I’ve made one. It is based on the original actionscript.xml and the Flash CS3 AsColorSyntax_3.xml file so it should have everything you can see colored on the IDE.
This edit mode doesn’t have any as2 specific keywords, so if you have to work on as2 don’t delete the original. Otherwise, you can just replace your original actionscript.xml file (you’ll find it problably in “c:\program files\jEdit\modes” if you’re on win xp) with this one. Make a backup of the original, just in case.
Grab the actionscript 3 edit mode for jEdit