From Politico.com:

Democrats moved Thursday to give special relief to the financially strapped Postal Service, which would be allowed to defer $4 billion in payments due at the end of this month to cover retirement benefits for its employees.

Republicans protested the bailout but made no significant effort to block the provision, which has now been attached to a stop-gap spending bill slated to come before the House and Senate in the next week.

This isn't the first time, nor the largest amount that that USPS has requested this year:

The U.S. Postal Service — known in the tech world as “snail mail” — is in the midst of a financial meltdown of its own... The postal service has asked Congress for $25 billion over eight years in financial relief...

The GAO called for quick action in two areas: trim compensation and benefits, and improve mail processing. The postal service has said it is reviewing its entire business model.

These bailouts should come as no surprise, esepecially considering only 5 members (PDF) of the 111th congress are accountants by profession.  None were listed as a Mathematician.