Creating an Extension GRADD

An extension GRADD can be added to the system without interfering with 
normal operations. The extension GRADD works in the same manner as a 
normal GRADD. The extension GRADD identifies itself to the system via the 
pszFunctionClassID field of the CAPSINFO data structure. This structure is 
returned to VMAN via GHI_CMD_QUERYCAPS. 

The extension layer communicates with the extension GRADD in the same 
manner described in the "Adding Extensions to an Existing GRADD" section 
earlier.