The easiest way to solve this is to just upgrade.
You will not lose any existing data doing this.
1) Download
PostgreSQL 8.4.8-1 (Mac)2) Double-click the dmg file and it will open up a new finder window.
3) Double-click the installer postgresql-8.4.8-1-osx
4) If you get a warning click open and if you are prompted for your admin password enter it.
5) Click "Next >" about four times, then wait for it to install.
6) Uncheck the "Launch Stack Builder?" at exit checkbox.
7) Click Finish.
If everything completed with no errors you should be able to run PT3 as normal. Note you can reinstall PostgreSQL as much as you want and it will not delete your data
as long as you never uninstall first.If you continue to have trouble please post the last few entries from your Console log again.