Lennon struck a minute into injury time just when it looked as though Fabricio Coloccini's 59th-minute strike had handed the Magpies all three points.
Coloccini controlled Danny Guthrie's cross on his chest before smashing a shot past Carlo Cudicini.
However, just as they had done last Sunday at Sunderland, Alan Pardew's men conceded in stoppage time to let two points slip from their grasp.
Toon substitute Nile Ranger wasted a glorious opportunity to secure victory in the final minute of normal time and the miss proved costly when Lennon cut inside and blasted a right-foot shot past Steve Harper to snatch a point.
Leon Best and Luka Modric both it the bar and the Magpies were indebted to Harper for some fines saves.
Source: PA
Source: PA