How to setup VNC for Mac

I currently have Froyo on an Evo 4g. I created a VNC Computer for the Mac on the Pocketcloud app. I put my external ip on the Host address. I also opened port 5900 on my router and set the operating system to Mac on the phone. I have OS X 10.6.5. I also have PocketCloud application running in the Mac. I have also gone into the Sharing settings to allow remote management. I still cannot connect so what am I missing or need to do on the phone or mac side to fix this problem?