I want to write a C3PO which customises the context menu that users get
when they right click on a message in the main Mailbox.

I've used the C3PO wizard and there is appropriate code in the
CustomizeContextMenu routine in the CommandFactory class but this routine
doesn't seem to be called when the user right clicks on a message (I've
put in some diagnostics to tell me when it it triggered).

I can use the same CustomiseContextMenu routine to customise GW.CLIENT
context menus, so I'm sure my code is correct, but it doesn't work in a
GW.MESSAGE context.

I'm stumped, I've read the documentation and as far as I can see this
should work, what am I missing ?

Thanks very much.