Nikola Zigic, reputedly the highest paid player in the Championship, should have justified his weekly wage and spearheaded Birmingham's first home win in four games.
Instead, the Serb missed a gilt-edged first-half chance which enabled Forest, who have their own goalscoring problems, to hang on for yet another draw.
This was Birmingham's fourth successive home draw and explains why they are still in the bottom half of the table.
It was not Forest's day and seven minutes from time substitute Darius Henderson was sent off following a tackle on Birmingham's veteran skipper, Paul Robinson, who was booked for retaliating.
Watched by their biggest home crowd of the season Birmingham enjoyed more of the game than Forest but failed to capitalise upon several good chances despite some inspirational play by their youngsters, Jesse Lingard and Oliver Lee.
Forest went into the game with only one defeat in their previous six matches and in the early stages displayed several promising smooth attacks in which Andy Reid, as usual, was the instigator.
As a result Birmingham found themselves involved in a defensive battle in their bid to quell some dangerous attacks.
But it was Birmingham who went closest to opening their account in the opening 20 minutes when Tom Adeyemi's looping header following a Chris Burke corner dropped on the back netting.
Forest were in no mood to stand on any ceremony as they put in several strong tackles. Dan Harding brought down Lingard and escaped a booking but was not so fortunate when he later hacked down Burke.
From the free-kick Kyle Bartley demonstrated his potential danger with a strong downward header which Karl Darlow saved with his legs.
Darlow was again in action a couple of minutes later when he pushed away a dangerous left footed, dipping shot from Burke.
This was a positive spell of attacking play from Birmingham who gained in confidence after surviving Forest's early onslaught.
They should have taken a 37th-minute lead when Zigic inexplicably missed a Burke head-high cross from just a few yards in front of Forest's goal.
As a result of Birmingham taking such a firm grip of the last 20 minutes Forest's strikers, Simon Cox and Jamie Mackie, found themselves isolated with no opportunities to make any kind of impact.
At half time Eric Lichaj was drafted in for Harding who had often come off second best against Burke and, like the start of the game, Forest were to the fore in the early stages of the second period.
Birmingham regrouped to pressurise Forest and only a dubious tackle by Jack Hobbs cut out the goalscoring threat of Burke.
Unfortunately, the game ended on a sour note with Henderson's reckless tackle on Robinson and his resulting red card after being on the field for only eight minutes.