SAN FRANCISCO (MarketWatch) -- Shares of Fannie Mae and Freddie Mac surged Monday after the government announced unlimited taxpayer support for the mortgage giants.

However, recently disclosed pay packages for Fannie FNM and Freddie FRE executives suggest the shares are worthless, Bose George, an analyst at Keefe, Bruyette & Woods, wrote in a note to investors.

Fannie Chief Executive Michael Williams and Freddie CEO Charles Haldeman got $6 million annual compensation packages, according to regulatory filings last week. See details of their pay.

To get all that money, the companies have to meet longer-term performance targets. But the packages don't include any stock, despite the fact that the government's pay czar Kenneth Feinberg has been pushing for more stock-based compensation to better align management and shareholder interests.

A portion of Williams' and Haldeman's compensation will come from "deferred salary," which is cash that will be paid only if Fannie and Freddie meet performance goals set by the companies' boards and reviewed by the Federal Housing Finance Agency, their regulator.

“ 'This reinforces our view that the common shares will eventually trade to zero.' ” — Bose George, Keefe, Bruyette & Woods

This is supposed to replicate "stock salary" that Feinberg approved for executives at companies that benefited from huge government bailouts. However, because of Fannie and Freddie's "unique circumstances," this part of their CEOs' compensation will be in cash, the Federal Housing Finance Agency said in a Dec. 24 statement.

What makes Fannie and Freddie unique is that the companies can't issue new common stock for executive compensation without getting Treasury's approval first. But that probably wasn't a "meaningful impediment," KBW's George noted.

"The more obvious reason is that the shares have no long-term value and that no executive would accept unvested shares of the companies as part of their compensation package," the analyst said.

"This reinforces our view that the common shares will eventually trade to zero," George concluded. "The companies will never be able to repay the government."