You can use Firefox for testing in a Mac but you may have to do this :
"Posted: Thu Sep 10, 2009 1:17 pm Post subject:
Firefox for Mac appears to be a bit buggy still and it does not seem to recognize the compressed version of our Javascript file. As a workaround you can do the following:
1) Rename the file AwareIM.app/Contents/Resources/Java/Tomcat/webapps/AwareIM/aware_ext/aware.js to aware_min.js
2) Rename the file AwareIM.app/Contents/Resources/Java/Tomcat/webapps/AwareIM/aware_ext/aware_full.js to aware.js
3) Refresh the browser
Aware IM Support Team"