only omniweb beta has the compatibility control panel. in my experience, iTools work fine with omniweb but only when you tell omniweb to use the netscape user agent. spittys description of how to do this is correct.
on a related note, i think its a little annoying that apples own website doesn t allow omniweb, when omniweb has been the default browser for OSX up until OSXPB, and the only browser available for many years. omnigroup has supported apple, i think apple should return the favor. javascript support in omniweb is not great though, and this release is only a beta, so i m not too annoyed.