Testing eBlast on Outlook from a Mac?

I have a new client whom I create several HTML eBlasts for every month. The last one I created looked perfect in Thunderbird, but evidently went wonky in Outlook. Is their any website (like IE Netrender) or any program that I can use to verify appropriate layout for Outlook?

I'm running Leopard on an iMac G4 if that is helpful.

Help is much appreciated.