The Senate Homeland Security Committee cut off consideration of a bipartisan postal measure on Wednesday, after lawmakers requested changes to two amendments.

{mosads}The panel, in an at times spirited mark-up, considered close to a dozen amendments before calling it a day, and the committee’s chairman, Sen. Tom Carper (D-Del.), has yet to say when they’ll pick the measure up again.

During the mark-up, both Carper and the committee’s top Republican, Sen. Tom Coburn (Okla.), suggested it had been a struggle to get a bill ready for mark-up.

Carper and Coburn first released their postal measure in August, and Carper has been forced to delay several mark-ups in recent months

The most recent effort, Carper said, “is not the proposal I would put forward if I had my way. I’m sure Dr. Coburn and the rest of my colleagues would say the same thing.”

For his part, Coburn said that he’d never worked on a measure as long as the postal proposal.

In their bill, Carper and Coburn seek to give the Postal Service – which lost $5 billion in fiscal 2013 – relief from the required prepayments for future retiree healthcare that have accounted for a majority of the agency’s losses the last couple of years.

The measure would also give the Postal Service more latitude to raise stamp prices and to roll back delivery standards, create a new health benefits program, give the agency new revenue streams and try to smooth out the collective bargaining process.

An amendment from Sen. Rand Paul (R-Ky.) that would allow private citizens to carry guns in the public areas of post offices, as long as that was allowed by state and local laws, is one of the two that needs to be modified.

“Some lawmakers wanted the language to be more specific and Senator Paul is working on addressing those concerns,” a spokeswoman for the Kentucky Republican said.

The other amendment that needs modifying is from Sen. Tammy Baldwin (D-Wis.), who opposes the proposals that give the Postal Service more oversight over its pricing structure.

Both postal unions and the mailing industry have said they oppose the Carper and Coburn measure as currently written.