Mozilla makes desktop Firefox available for Windows, Mac and Linux. For AIX availability, you would have to check with IBM or whatever third-party source supplies it. Apparently, IBM only makes Firefox 3.5.13 available: http://www-03.ibm.com/systems/power/software/aix/browsers/index.html Older and newer versions can be downloaded from third-party sources, but version 3.0 doesn't seem to be available: http://linkitup.de/ForAIX/Firefox/ Versions of desktop Firefox currently supported by Mozilla * http://www.mozilla.org/en-US/firefox/all.html * https://www.mozilla.org/en-US/firefox/organizations/all.html * http://www.mozilla.org/en-US/firefox/all-older.html