I am still not confident that mail sent out from Cactus-Mall.com is working 100%. Detecting bounces has been made more complicated in that a kind German spammer has directed the bounce messages from their spam onto a cactus-mall address so that genuine bounces are buried in piles of junk. Inward coming email to cactus-mall is unaffected.
I have sent a few messages out from an apparent cactus-mall.net address. Please do no reply to that address - it won't work - there is no mechanism for mail to be accepted or forwarded at that address.