this is what i found in the php manual
(i was looking for some info on the mail function 🙂 )
"sendmail_path string
Where the sendmail program can be found, usually /usr/sbin/sendmail or /usr/lib/sendmail configure does an "
it auto configures it i guess
"honest attempt of locating this one for you and set a default, but if it fails, you can set it here.
Systems not using sendmail should set this directive to the sendmail wrapper/replacement their mail system offers, if any. For example, Qmail users can normally set it to /var/qmail/bin/sendmail."
dunno if it helped