The U.S. Army’s efforts to move to new, single enterprise email service would be halted, at least temporarily, if language in the 2012 defense authorization bill approved by House and Senate negotiators Monday goes into effect, according to a report by Federal News Radio.

The legislation orders Army Secretary John McHugh to designate the service’s enterprise-email transition as a formal acquisition program, which would be overseen by the Army’s assistant secretary for acquisitions, logistics and technology, rather than under the direction of the Army’s G-6 CIO office.

That would complicate the Army’s ongoing efforts to move from an its fragmented collection of email systems to a single, unified email system being developed and operated by the Defense Information Systems Agency to host the Army’s enterprise email application.

So far 220,000 of 1.4 million Army users (including those at Fort Rucker) have migrated since March, Krieger said during the Federal Executive Forum last month.

The move is saving the Army $100 million this year alone on enterprise email operating costs, according to Mike Krieger, deputy chief information officer, G-6, U.S. Army.

The Army has been hobbled for years by legacy email exchange systems that prevented soldiers and civilians from being able to have a single secure email account follow them wherever they moved from base to base or to theaters abroad. Efforts over the past several years to move to a single system have foundered due to a combination of technology and contracting hurdles that resulted in Army officials having to rethink or restart their efforts.

This time, according to the Federal News Radio report, the Army would be required to establish a formal acquisition oversight body for the program, certify that its enterprise email program has been subject to the “maximum amount” of full and open competition possible and assess the relative costs of the DISA-provided service compared to alternatives.

The report went on to say:

Until those requirements are met and the Army reports back to Congress, the service would be barred from migrating any more of its email users from legacy systems to the new DoD cloud environment. Though not expressly specified in the bill, House-Senate conferees said their legislation would not affect the hundreds of thousands of users who have already made the move.