Handling a specific Windows message in Common Graphics

Today I installed the ACL 7 trial version to investigate processing a
specific Windows message that my application must monitor:
WM_DEVICECHANGE. This message is sent to all active windows by the
operating system when, among other things, storage devices are added
and removed from the system.

I was delighted to find that there are methods defined for a huge
number of Windows messages in the "win" package¹, but sadly
WM_DEVICECHANGE has yet to be included. Is there some way to add such
a method for the message, or perhaps use some default catch-all
function that receives all Windows messages not covered by the
predefined methods?

Of course, there are several related structures that would need to be
defined to pick apart the arguments to WM_DEVICECHANGE, but that's not
worth worrying about until I figure out how to catch the message to
begin with.

Please advise.


Footnotes: 
¹ Handling Low-Level WinAPI Messages
  http://www.franz.com/support/documentation/7.0/doc/cg/cg-events.htm

-- 
Steven E. Harris