Hello,
i registerd me some minutes ago and get my used password in plaintext via email.
PLEASE do not do this because of security reasons!
Everyone is able to read unsecured communications - as long as you do not send the emails via a secure protection (and i know that you cannot do this easily) you should never send passwords via email.
You already mentioned in your registration/activation email that if one forgot its password he easily can create a new one on your page.
So i really recommend NOT to send any password via email!