A Mobile, Ala., woman has filed a federal lawsuit against Comcast over the company’s requirement that subscribers lease set-top boxes for premium services.

The lawsuit, which was filed in Mobile’s federal court by plaintiff Gloria Cordier and her lawyer, Stephen Mullins, said that Comcast is violating the Sherman Antitrust Act by forcing customers to pay a monthly rental fee for a set-top box in order to watch premium channels, according to a story in today’s Mobile Press-Register.

The lawsuit takes issue with Comcast and other cable operators requiring customers to lease set-top boxes from them, even though they are available at retail outlets.

The Federal Communications Commission’s “separable security” mandate went into effect in July 2007, which required cable operators to include removable CableCards in the set-top boxes. In granting a waiver to Evolution Broadband earlier this month (story here), the FCC conceded that, to date, there isn’t much of a retail market for set-top boxes.

The lawsuit, which Mullins said could be consolidated with other similar suits, contends that Comcast improperly promotes its leased set-top boxes as superior to the ones with CableCards, and requires subscribers to lease the boxes with CableCards, as well, according to the Press-Register.

Comcast didn’t comment on the lawsuit by deadline.