You should provide a sample capx describing your problem for more efficient help next time ;)
To start with, how do you do your shoot ? Did you add a turret behavior on your character ? How does your bullet move ? With a bullet behavior ? If so, you have to change the "angle of motion" of the bullet when you spawn it.
For this, do something like that : <img src="http://imageshack.us/scaled/landing/46/enk3.jpg" border="0" />