Enumeration of Keyboard Keys?

[Jim Orcheson <jim va3hj ca>]

I have been creating a number of menu items with accelerator keys. I 
would like to use the Delete key as an accelerator but I cannot find an 
enumeration or definition in gtkmm for it and other non-printing keys.

gtk+ has GDK_Delete but the header file that this is in does not appear 
to be included in gtkmm. Is there a key enumeration in gtkmm? If so, 
where is it? If not, what do I have to do to get a value for the key?

Thanks in advance,

Jim