BetterZip can already create RAR archives. You only have to download the rar commandline tool for Mac OS X, extract it to your hard disk, and tell BetterZip where it is. Locate it in the Preferences window on the tab Helpers. BetterZip does not include a license for the RAR commandline tool only for unrar.

Oh, awesome!!!!
I had a feeling that it could do it, but having a ferly good look thou your site I couldn't find it.

Thanks heaps!!! I might even consider buying this app now!

Oh, BTW that website you gave has a REALY old version of winrar, I found this site: http://www.rarlab.com/download.htm It has the winrar file in there too, and it was last updated this year and and supports intel unlike the other one.

Yeah, it used to be an older version, but they seem to have updated the link recently without changing the file size. I just downloaded it and checked before posting the link. ;-) It's the current version.