Proper configuration of safe mode

Hi, I'd like to enable safe mode in my current setup but it seems that I am doing something wrong. I have configure a webmail (IMP) and I can access my messages fine but when I try to send a new one I get error message in my log Jul 12 15:00:44 HORDE [error] [imp] sendmail [/var/www/phpexecdir/sendmail] is not a valid file [on line 1042 of "/var/www/html/horde/imp/compose.php"] My webserver configuration <Directory /var/www/html/horde/>

              php_admin_flag safe_mode On
              php_admin_value upload_tmp_dir "/var/www/html/horde/tmp"
              php_admin_value safe_mode_include_dir

"/usr/share/pear:/var/www/html/horde/"

              php_admin_value open_basedir

".:/usr/share/pear:/var/www/html/horde/"

              php_admin_value safe_mode_exec_dir

"/var/www/phpexecdir/" </Directory> I have copied sendmail from it's original location to this new one. Any tips?