How to join two domains?

[Andrius Kurtinaitis]

Hello,

I am solving a problem where I need a chess-table-like grids:
the 2D domain should consist of the points (i,j) where (i+j) mod 2 == 0 
or 1.
No built-in POOMA domain type (except Grid) supports such domains. And 
Grid construction is too complex. And its iteration is probably not 
optimal. However, I could create such a domain by "joining" two 2D 
Ranges. I was also unable to find out, how to do that, either.
Thank you for any help you can provide.

Andrius Kurtinaitis

P.S. Am I on the correct list asking the questions? pooma-dev - sounds 
to be only for the POOMA authors. Is there some other list for users?