Question about COLLADA's rigid_constraint in Bullet

[dodo]

I read the specification of COLLADA and found the following
example about rigid_constraint in page 186 of COLLADA's
specification,and I read same example in presentation of COLLADA
Physics 2007 web3d:
----------------------
<rigid_constraint sid="rigidHingeConstraint">
<ref_attachment rigid_body="#wallRigidBody">
<translate sid="translate">5 0 0</translate>
</ref_attachment>
<attachment rigid_body="#doorRigidBody">
<translate sid="translate">0 8 0</translate>
<rotate sid="rotateX">0 1 0 -45.0</rotate>
</attachment>
........................
I added similar sections of rigid_constraint in a dae-file. But
these sentences could not be loaded in Bullet's Colladademo. I am very
confused and can not find more explanation about rigid_constraint, so
write this email for a help from you.
Could you please give me a help and sample of COLLADA including
rigid_constraint's function, which can be used in Bullet's
Colladademo?