L293 HBridge only outputs 3V?

... i'm trying to have a cd-player-tray motor be controllable via arduino / serial.

pretty much the same setup as here, other voltages though:
http://itp.nyu.edu/physcomp/Labs/DCMotorControl

motor and arduino both have external power.

i'm using this standard cd-player-tray motor (5.9V):
RF-310T-11400
http://www.mcmelectronics.com/product/28-1920

i actually have to supply the bridge 12V on pin 8 (VCC2) to make the motor turn ok. if i connect it directly to the power source it has much much more torque.

any idea what i could do?

F