Soulskill from the convenience-charge-for-different-bits dept.
An anonymous reader writes "AT&T is sending warning notifications to jailbroken iPhone users who use unofficial tethering methods like MyWi and PDANet. 'Customers are being notified that their service plans need updating to subscribe to a tethering plan, and that they will be automatically subscribed to a DataPro 4GB package that costs an additional $45 per month if they continue to tether.'"
If it happens once, it's a bug. If it happens twice, it's a feature.
If it happens more than twice, it's a design philosophy.