The Secret Service had a bigger job than protecting the Obama family last night.

After Jay-Z finished rehearsal for his pre-inaugural concert, he and wife Beyoncé found out police had shut down streets around the Warner Theater. Cops told the star couple they’d have to walk four blocks to meet their driver.

“Beyoncé wouldn’t walk in high heels in the cold,” says our spy. “The cops wouldn’t budge, but the Secret Service agreed to let the driver pick Jay and Beyoncé up, bring them to their hotel so they could change, and get them back to the theater.”

How cold was it? Before he went on, Jay-Z was supposed to leave his hand prints in a block of cement destined for the theater’s star-studded sidewalk. But the cement froze.

Jigga, who wowed the crowd with surprise guests Young Jeezy, John Legend, Mary J. Blige and the missus, told us he spoke Sunday with President-elect Obama: “He had an eagerness about him. He really wants to get to work.”