I'm not sure if I totally understand your post but I know when I first set up my Gmail account I was getting a copy of emails that I sent on my phone. I simply set up a filter in BIS. I labeled it My sent Gmail Msgs & had the "From" field containing my gmail address, then set it to not forward those messages to my Berry. I now no longer get that sent Gmail message. Hope that helped, but if it didn't could you be a little more specific?
Apparently this was fixed with the recently BIS update. You need to remove your email account from your backberry and reinstall it. Then you shouldnt have that issues again.