Damping function for World in Bullet???

[saurabhshukla]

Hi, i am new to Bullet physics. I am converting a ODE project into Bullet. In ODE there is a function dWorldSetDamping() to set world's damping but in Bullet i found only
void btRigidBody::setDamping ( btScalar lin_damping,btScalar ang_damping ) function. This bullet function is used for setting damping of Rigid bodies not for world.
Now my question is that Is there any function by which i can set world's damping? or world damping not supported in Bullet physics?
Please help me. Any help appreciated.