Sylvan Ebanks-Blake missed the best chance of the match, firing over from 12 yards, while keeper Colin Doyle denied the visitors with vital saves at the death at St Andrew's.
In a game of few chances, Sylvan Ebanks-Blake missed by far the best chance when he hit Michael Kightly’s cross over from 12 yards and Birmingham goalkeeper Colin Doyle made a fantastic double save in stoppage time, first tipping substitute Matt Jarvis' shot onto the post and then denying fellow substitute Steven Fletcher with the rebound in the dying seconds.
Both managers made plenty of changes to their sides for this fixture. Mick McCarthy brought in Dorus De Vries for Wayne Hennessey but kept his back four unchanged meaning a start for captain Roger Johnson against his former side.
Kightly, back from his loan spell at Watford, came in for Adam Hammill and Eggert Jonsson made his debut replacing Emmanuel Frimpong. Stephen Hunt replaced Anthony Forde and Ebanks-Blake partnered Kevin Doyle up front after replacing Dave Edwards.
Chris Hughton made seven changes to his side. In came Colin Doyle, Steven Caldwell, Nathan Redmond, Wade Elliot, Morgaro Gomis, Jordon Mutch and Adam Rooney for Boaz Myhill, Liam Ridgewell, Chris Burke, Keith Fahey, Jean Beausejour, Marlon King and Nikola Zigic.
The game began at a good tempo with both sides looking to get forward and get some balls into the area. The first shot on goal came about five minutes in when a Stephen Ward free kick was only cleared by Guirane N’Daw straight to Jonsson but from 25 yards he shot over the bar.
Mutch was the next to try his luck but he could only guide Murphy’s cross over the bar from a difficult position inside the area. At the other end there was a loud cheer from the home fans when Johnson headed Kightly’s left-wing corner over the bar.
Johnson’s afternoon soon came to an end, though, after injuring his ankle upon landing following an aerial collision with Rooney. It was a sad way to end his return to St Andrew's having made such a commanding start but amidst the chorus of boos some supporters did applaud him as he hobbled off to be replaced by Kevin Foley.
Minutes after the restart Doyle made the first save of the afternoon. Ebanks-Blake battled his way past Curtis Davies and shot low at the near post but the keeper managed to kick his effort away.
Further shots from Doyle, which went horribly wide, and Redmond, which produced an easy save for De Vries, were the last actions in a first half which saw lots of endeavor but little goal mouth action.
Birmingham was pressed into an early substitution at the beginning of the second half with Ridgewell hobbling off to be replaced by Caldwell.
With an hour of the game almost up and no side looking like breaking the deadlock, Ebanks-Blake missed a glorious opportunity to give Wolves the lead.
Kightly was given acres of space down the right with Murphy not closing him down and his ball across the area was met by the striker just 12 yards out and with just Doyle to beat he scooped his shot over the bar.
McCarthy introduced top scorer Fletcher into the game for his final throw of the dice as the disappointing Doyle made way. The home fans were soon on their feet to applaud N’Daw as he came off with Fahey coming into midfield.
With four minutes of added time signaled by the fourth official, Birmingham finally tested De Vries but Redmond's shot was straight at the keeper who made a routine save.
But there was some late drama as the visitors hit the post right at the death. Doyle made an incredible double save, first tipping Jarvis' shot on to the post and then getting up quickly to deny Fletcher what looked a certain winner as he headed the rebound towards goal.
The final whistle blew moments later to end the contest which had been played out in front of under 15,000 supporters meaning the two teams will meet again at Molineux to decide who will move on to the fourth round of the cup.