One of the big advantages to jailbreaking has been the ability to enable tethering without carrier support. That doesn’t mean the carrier is unaware of the way the phone is being used. In fact, AT&T has started sending text messages to customers who are tethering without the company’s tethering plan.

The message reads as follows:

“Did you know tethering your Smartphone to a computer requires a tethering plan? Pls call 888-860-6789 for details or visit att.com/dataplans.”

Some customers are also receiving emails about the usage, alerting customers that they will be automatically enrolled in the DataPro 4GB plan if they don’t get in touch with AT&T. From the email:

“If we don’t hear from you, we’ll plan to automatically enroll you into DataPro 4GB after March 27, 2011. The new plan – whether you sign up on your own or we automatically enroll you – will replace your current smartphone data plan, including if you are on an unlimited data plan. If you discontinue tethering, no changes to your current plan will be required.”

AT&T says the goal is fairness to customers. Yes, they would like to screw all of us equally.