Open up the chars CNS file and look for something like this...
[Velocity]
walk.fwd = 2.4 ;Walk forward
walk.back = -2.2 ;Walk backward
run.fwd = 4.6, 0 ;Run forward (x, y)
run.back = -4.5,-3.8 ;Hop backward (x, y)
jump.neu = 0,-8.4 ;Neutral jumping velocity (x, y)
jump.back = -2.55 ;Jump back Speed (x, y)
jump.fwd = 2.5 ;Jump forward Speed (x, y)
runjump.back = -2.55,-8.1 ;Running jump speeds (opt)
runjump.fwd = 4,-8.1 ;.
airjump.neu = 0,-8.1 ;.
airjump.back = -2.55 ;Air jump speeds (opt)
airjump.fwd = 2.5 ;.
The higher the number the faster.