If I remember correctly Alltel uses AT&T as it's backbone provider. AT&T is
in the habit of sneaking around and putting up temporary blocks on various
types of P2P, as well as helping the NSA eavesdrop on your phone. If that's
what's happening to you then the block should probably come down in a week
or two. In the meantime you could experiment with other types of P2P such
as BitTorrent and Edonkey, and get acquainted with Alltel's newsgroup servers
too. ;]