Two macs, one can connect to iPhone update server, one cannot
We have multiple macs and iphones in the house. One mac can connect to the iphone update server without any problems. the other cannot. Both are on the same network. Both have identical firewall settings. One mac can manually download the iphone update file; the other cannot. Anyone have any idea what could be keeping the other mac from connecting to the download server? The other mac has no network problems with any other sites, only Apple's download server.
Suggestions would be appreciated. Thanks.
Macbook Pro, Mac OS X (10.5), 2 GB RAM, 250 GB HD, 17 inch Core Duo