West Ham owners David Sullivan and David Gold were denied the perfect post-Christmas present on their return to their former club.
The Hammers joint-chairmen were back at St Andrew's together for the first time since selling to Carson Yeung in November 2009 and subsequently taking charge at Upton Park the following January.
And they were celebrating after just four minutes as Carlton Cole capitalised on hesitancy from Pablo Ibanez to put the Hammers ahead, just as he had done in the Carling Cup semi-final second leg between the two sides at the start of 2011.
Birmingham launched a remarkable fightback to turn that tie around and, after an impressive albeit not quite repeat comeback, defender Murphy headed home an 81st-minute leveller to grab a deserved share of the spoils from what was a thoroughly entertaining encounter.
Victory could easily have gone to either side but a point apiece was a fair reflection and extended City's unbeaten run on home soil while West Ham, boasting the best away record in the second tier, moved back into second place behind leaders Southampton.
Amid a blistering start to proceedings, both teams created early openings as Chris Burke sent a header off target before Hammers skipper Kevin Nolan narrowly failed to connect with Julien Faubert's low, teasing cross.
And the deadlock was soon broken out of nowhere as Cole nicked the ball of a hesitant Ibanez before racing clear and dispatching the perfect finish past Boaz Myhill.
It was proving to be a free-flowing, open encounter in front of the 20,214 present, both defences snuffing out half-chances at either end, although West Ham were enjoying the better of proceedings with Cole causing City all sorts of problems.
Faubert somehow missed a great headed chance to put the visitors 2-0 ahead midway through the half before Ibanez cleared Frederic Piquionne's nodded effort off the line from the resulting corner.
Murphy's goalbound free-kick forced Robert Green into action for the first time before Keith Fahey's volley tested the Hammers stopper during a sustained spell of pressure from the home side.
The visitors had gone quiet over the second quarter but Myhill was called into a great stop in first-half injury time to deny Cole's quickfire effort.
The second half started in the same fashion as the first as Burke curled an effort inches wide before Steven Caldwell and Joey O'Brien made last-ditch tackles at either end.
Blues boss Chris Hughton turned to Nikola Zigic in an attempt to change things around.
Caldwell saw a header cleared to safety from Burke's corner before Myhill was again called upon to to parry substitute Henri Lansbury's strike to safety.
Zigic looped a header on to the roof of the net from Murphy's cross and, after Fahey tested Green, the Serbian somehow missed a gilt-edged chance from close range after James Tomkins' sliced clearance.
But a leveller finally arrived nine minutes from time as Murphy converted Burke's corner to send the home crowd into raptures, with Marlon King missing a late chance to snatch all three points.