Oh wait...I think I just remembered the solution to this.  We were skipping something...:

1.  Back up any old wallet.dat files you may have on the mac to a different directory
2.  Close the qt wallet
3.  Delete the contents of the ~/.bitcoin/ directory
4.  Paste the linux-generated wallet.dat file in the folder
5.  Restart the qt wallet & give it time to rebuild the block chain - this may take a while

If all goes according to plan, you'll start seeing your coins coming in as the chain reloads. 

Important:  This method is only suggested if you have NO coins in the mac-generated wallet to start.