The Digital Millennium Copyright Act strikes again.

Effective this week, a temporary provision that protected consumers taking their existing, newly-unlocked phone to another carrier has expired. As a result, anyone who attempts to unlock a cell phone without permission could be liable for up to $1,000,000 in fines, imprisonment for up to ten years, or both. Phone companies are exempt, but the customers who purchase phones from them are not.

The DMCA was never specifically written to stop customers from moving phones between wireless companies, but because its provisions are so broad, the Act caused a number of unintentional problems that leave copyright lawyers at the Electronic Frontier Foundation scratching their heads.

“This shows just how absurd the Digital Millennium Copyright Act is: a law that was supposed to stop the breaking of digital locks on copyrighted materials has led to the Librarian of Congress trying to regulate the used cellphone market,” says EFF attorney Mitch Stoltz.

The DMCA’s overly broad provisions are slightly tempered by the Library of Congress, which maintains an extensive exemptions list designed to cover for the law’s more ridiculous overreaching consequences. But those exemptions only last three years, and the one covering cell phone unlocking expired Sunday.

Jailbreaking your phone to strip away carrier-installed and mandated bloatware remains technically legal, but you won’t get far taking your phone to another provider without getting your current carrier’s permission. Some companies will gladly unlock cell phones for customers who have maintained an account for a certain number of days or have fulfilled their two-year service contract. But not all.

If your current phone company wants you to stay, your only recourse may be to buy a new cell phone from your new provider, who may never want you to leave either.