while sending a mail from a testmailscript, i got the error:
Warning: mail(): Permission denied: unable to execute shell to run mail delivery binary '/usr/sbin/sendmail -t -i' in /home/rawfox/public_html/test/testmail.php on line 13
The error message looks a bit more fundamental than sendmail permissions. It appears that the mail() function invokes a shell to run the sendmail command, and it's unable to run the shell judging by the error message. So it's not getting anywhere near sendmail itself. Is the shell (/bin/sh perhaps?) accessible to your PHP scripts? Is your web server running chrooted perhaps?
Paul.
