Blackburn came from two goals down to rescue a vital point in a thrilling game for the watching TV audience, but it was not enough for them to climb off the foot of the table.
Ewood Park is the place to be at the moment if you want excitement, with 18 goals in the last four Blackburn home matches, but the hosts certainly made life difficult for themselves after a dream start.
There were only four minutes on the watch when Paul Dickov cleverly dummied man of the match Steven Reid's low pass for the returning Matt Jansen to bury a left footer beyond Maik Taylor.
But three Birmingham goals later and Mark Hughes' men were booed off the pitch at half-time with seemingly little hope of an improved performance.
However, galvanised by Reid and Dickov, Blackburn bounced back almost immediately.
Reid pulled a goal back on 57 minutes, racing onto substitute David Thompson's pass to finish emphatically - all be it with the help of a deflection.
Thompson was heavily involved in the equaliser too, hoofing over the top for Dickov. The ex-Leicester striker wrestled with Kenny Cunningham but managed to squeeze the ball past Taylor, although it needed a final touch from Paul Gallagher to get it across the line.
In a frantic final half hour, either side could have won the game. First Reid's vicious drive from distance was parried by Taylor but no-one was following up and then Robbie Savage hit the post on 75 minutes with an overhead kick.
In the very last seconds, Dickov latched onto Barry Ferguson's pass behind the Blues defence, only for Taylor to race out and smother his effort.
Blackburn boss Hughes was pleased not to lose but said his side should have capitalised on taking the lead.
"We got off to a perfect start and should have kicked on from there," he reflected. "Instead we went backwards.
"We did some very good things today but there were far too many bad things as well." Birmingham had earlier shown great character to come back from the early setback of going behind but will be bitterly disappointed to have thrown their lead away.
First on the scoresheet was Darren Anderton after 17 minutes, profiting from some sluggish Blackburn defending to convert from close range after David Dunn flicked on Jesper Gronkjaer's cross.
After Damien Johnson had forced Brad Friedel to scoop his shot around the post, Birmingham notched two quick-fire goals with Mario Melchiot the architect.
Twice in the closing minutes of the first half the Dutchman's surged past Jay McEveley. On 38 minutes he set up Savage to hook in with the Blackburn defence non-existent and he then provided Dunn with the opportunity to notch on his first return to his old club.
Birmingham manager Steve Bruce admitted it was frustrating to see his side throw away a two-goal lead, particularly as Blackburn looked a beaten team at the interval.
"Before today we had the best defensive record in the league so when we went 3-1 up it was disappointing that we didn't see the game out," he said.
"We're very disappointed because from that position we should have won the game."