Gmail for Domains overactive with Spams

Oinam.com got invited to Gmails for Domains about a week back and everything else is working save for few issues of outgoing mails with Thunderbird (haven’t found a solution yet). If anybody have a solution to that, let me know. Well, the next issue is that Gmail is so active with spam that I got a bunch of authentic mails got netted in the Gmail Spam Filter. After seriously searching for the lost mails, I finally peep into the junk folder to find a bunch of non-spam mails.