I have just finished testing shaw to shaw, and it works fine for me. However, I did not send the emails from my phone as part of the test (since, under real situations, you won't have the phone anyways, so I used webmail.shaw.ca to send the BuddyGuard command messages. Both shaw addresses are valid on my BB (set up in BIS).
My command emails were deleted by BuddyGuard as expected and were acted upon by the application. My reply email was not, which is acceptable because under real circumstances it would not be wise to use an address that is on your BB to send commands from. As I mentioned earlier, I use a gmail account which is NOT set up on my BB to send commands from. I can however, send those commands from that gmail address TO any of the email accounts set up on the BB (I have tested 4 now: two shaw.ca, 1 gmail, 1 rogers.blackberry.net).
Two things which I mentioned previously:
1) are you using BIS filters to filter out duplicate sent mail for all your shaw addresses? Here is a post explaining how to do it and more importantly, why. You may be looking at the duplicate email instead of the original email (which BuddyGuard already acted upon), thinking that BuddyGuard is not working.
http://www.labnol.org/gadgets/phones...ry-inbox/1520/
2) I would recommend not using shaw.ca addresses due to BIS polling delays. Personally I use gmail to send commands from (again, using an account not on my BB) and send to my @rogers.blackberry.net address instead of my three shaw.ca addresses amongst others on my BB. Mail sent to your BIS account (in my case, @rogers.blackberry.net) is instantaneously sent to your BB where BuddyGuard can act upon the command and reply; whereas shaw.ca accounts are polled for every 2 - 12 minutes. Gmail and Yahoo addresses are just as good but other ISP's poll time may vary like shaw's does.
Hope this helps; if not, feel free to PIN me as I think we've highjacked this thread...