[pun_newpost_mail_notify] Spam detected

Hi,

I've installed this extension : pun_newpost_mail_notify

I've a problem, when i activate this extension and when i post a new message, e-mail don't sent :

warning mail() [function.mail]: Spam detected, mail don't sent. in .../post.php(240) : eval()'d code on line 36.

I use punBB 1.3.4 and extensions :
Admin add user
Antispam System
Attachment
Events registration
Logging of events
Post and registration approval
PunBB Repository
Send email to admin for each new post
Stop spam from bots

Thanks for your answers.