BellSouth recently joined other carriers in suing AT&T over two different regulatory matters, AT&T said in filings with the U.S. Security & Exchange Commission today.

Following a February 2005 decision from the Federal Communications Commission denying AT&T’s petition to declare its prepaid calling cards an interstate information service, Qwest Communications sued AT&T, claiming the interexchange carrier breached federal and state tariffs and private contracts.

“Recently, other carriers, including BellSouth, have filed similar lawsuits in various jurisdictions, all seeking unspecified damages,” AT&T said in filings today.

BellSouth also recently sued AT&T based on a 2004 FCC ruling denying the IXC’s petition to exempt certain types of IP telephony service from access charges. SBC sued AT&T on those grounds as well but settled the dispute along with a variety of others between the two merging companies in this year’s first quarter, when AT&T agreed to pay SBC $60 million.

During the second quarter, AT&T also paid $340 million to settle several claims brought against it by bondholders of the At Home Corp., the Internet service provider AT&T acquired in 2000 and sold to Comcast in 2002. That suit accused AT&T of breaching its fiduciary duties to At Home when it moved to transfer the ISP’s customers to its own network in advance of At Home’s impending bankruptcy. Comcast will split the settlement with AT&T, reimbursing the IXC for $170 million.