The Bitcoin network is a bit slow lately, so lower priority transactions may take a couple hours to find their way to a node which will accept them.
Rest assured, though, that your transaction IS in the network. You can see it here:
http://bitcoincharts.com/bitcoin/#c4b301cedade7f21de1b4daf79b9aa565f640908a370008c10cafee6bce845cfI'm sure it will get to you in a few blocks.