TOGGLING COORDINATES IN CONSTRAINT

Hi all, i have a problem of constraining my model with respect to a cylindrical co ordinate system.

FULL EXPLANATION OF PROBLEM: 

i have meshed a 3d model and have assigned force to the component and on the constraint part i have to assign constraints based on a cylindrical co ordinate system to the nodes on the surface to be constrained so for this i have populated the surface nodes to be constrained in a ENTITY SET  and in the Analysis----->System------->CREATE  i have created a Cylindrical co ordinate system and in Analysis----->System-------> ASSIGN  i have assigned the ENTITY SET to the created cylindrical coordinate system and now my objective is to allow the ROTATION FREE AND CONSTRAIN the other two DOF.

BUT  when i go to the constraints i cant find a toggle option to toggle between the global coordinate system to cylindrical coordinate system i can find only dof1 to dof6  and i tried to simulate the cylindrical coordinate system in Rectangular coordinate system  by removing the rotation dof i.e dof4,5&6 the result was not changed bcoz of the reason for a solid 3d component it is enough to constraint only 3 dof's and for this to allow the rotation in  one direction i have made the translation free in the other two direction

eg(X,Y,Z) to make rotation about X free i have made the translation free in Y and Z and this resulted in excessive displacement and so the only solution for my problem can be assigning a Cylindrical Coordinate system and locking translation movement and allowing rotational movement alone but am not able to find the place where i can toggle my co ordinate system from Global co ordinate to Cylindrical co ordinate.

Regards

Jeeva.B