How to merge two iphoto libraries on the same computer?

I just got all my data moved onto my new mac. However now when i try to open the photos in my old iphoto library it restarts my iphoto and my new pictures are no longer then. I have to quit and go to the other one to see my newer pictures. Is there a way to merge these so that they are in ONE library. Note: they are on the SAME computer.