How to prevent smtp from accepting blank From: field

[Manvendra Bhangui]

I am having a problem with my site where someone is trying to spam the site with some message titled "Snowhite and Seven Dwarfs". The From: field is being shown as From: [EMAIL PROTECTED]     I have put the entry [EMAIL PROTECTED] in badrcptto and also tested that mail from: [EMAIL PROTECTED] is not being accepted by qmail-smtp. However inspite of this mails keep on coming from this site. It seems that the the smtp dialogue is being done in he following manner (i.e. a blank mail from: is being given)   telnet 0 smtp Trying 0.0.0.0... Connected to 0. Escape character is '^]'. 220  ESMTP mail from: 250 ok rcpt to:<[EMAIL PROTECTED]> 250 ok data 354 go ahead From:Hahaha <[EMAIL PROTECTED]> Subject: Snowite and the seven dwarfs . 250 ok 984632317 qp 4283   Any suggestions on preventing blank mail from: being given during smtp dialogue?   Regards Manny