How to change the Transformation matrix.
I am using the PowerVR sdk for IOS.
I found the answer. This is what I did and let me know if it the good way.
PVRTMATRIX* anim = (PVRTMATRIX*)pMesh->getNode()->pfAnimMatrix;
PVRTMatrixMultiply(*anim, r, *anim);
And also use GetWorldMatrixNoCache instead of GetWorldMatrix