Alessandro Diamanti and Carlton Cole scored in each half of a pulsating encounter to give West Ham United three valuable points and lift the club out of the bottom three.
Gianfranco Zola had spoken of the need for his players to deliver on a freezing night in east London and they did just that and more. Diamanti set the Boleyn Ground alight with a stunning free-kick on the stroke of half-time before Cole wrapped up the win with a brave header midway through the second half.
Diamanti, playing on the left in place of the rested Jack Collison, was a considerable threat in the early stages while the other flank saw Julien Faubert given plenty of space to get forward. Home debutant Mido - in for the injured Benni McCarthy - was the most likely to get on the end, twice connecting with his head to crosses although he failed to trouble Joe Hart on either occasion.
Birmingham caused all kinds of mayhem in the home defence on 25 minutes with the right-back Stephen Carr allowed to surge into the box and tease a low centre across Robert Green's goal. The ball was hurriedly hacked away and the Hammers broke up the other end. Cole eventually knocked down for Diamanti to lash a shot that Hart just about clawed away.
Jerome combined with Kevin Phillips - one of three changes for the Blues, the first time in 13 matches that Alex McLeish had altered his starting lineup - and fired just wide from 20 yards as the half-hour mark. Cole went even closer for the hosts four minutes later, holding off Scott Dann before turning and shooting across goal - the ball just missing the far post.
If that was close, the chance that fell to Cole a minute later was even better. It dropped to him from a Diamanti cross in a central position, eight yards out, and his fierce drive seemed a certain goal until Scott Dann threw himself in the way. It was not frenetic stuff but the teams were trading chances, Phillips was next to threaten, lashing a long-ranger that Green had to palm over.
Hammers old boy Lee Bowyer was booked on 43 minutes for a foul on Diamanti but the knock did not deter the Italian winger too much. Deep into first-half added time, he stepped up to curl a 20-yard free-kick into Hart's top left-hand corner with the keeper nowhere near it after Dann had brought down Scott Parker. There was barely time for the restart before the half-time whistle.
Herita Ilunga, another of Zola's four starting changes, failed to reappear for the second half with Jonathan Spector reprising the left-back role he had filled in the previous three games. The second half began in similar fashion to the first with the sides trading opportunities - the best of which was a Craig Gardner free-kick punched away by Green on 55 minutes.
Cole, meanwhile, was thriving on having a strike partner in Mido and the England man was proving harder to handle as the contest wore on. On the hour, he surged away from three defenders before touching back for Diamanti to have a go. This time the radar was off and the former Livorno man's effort was wayward.
Mido's last act was to win possession and then race through. With Cole well placed, the Egypt striker instead sent a tame effort into Hart's hands. It was a sign of his exhaustion on his first start for the Hammers and Zola wasted no time in sending on Ilan - a substitute scorer against Burnley at the weekend - in his place.
The second goal was needed and it came within seconds of the changes. Cole stooping to head in from Faubert's cross after the Frenchman had combined superbly with Behrami before racing to the byline. It had a galvanising effect on everyone of the 34,458 in the crowd, bar the 800 or so Birmingham fans - with 'Come on you Irons' and 'Bubbles' ringing out around the stadium.
Behrami, like his midfield mate Radoslav Kovac, was one of the brightest performers and his run and shot on 73 minutes typified the adventure and determination in the Hammers ranks. Birmingham were not about to roll over though and three times in 20 seconds skipper Matthew Upson had to be alert to clear dangerous balls into the penalty area.
Cole was named man of the match to rapturous acclaim in the dying stages while Parker got an equally loud reception when he went off to be replaced by Mark Noble, who had made way for Kovac in the starting lineup. That was to be the last incident of note with another hearty cheer greeting the arrival of full time.