Adding option to default config.

Adding option for users that use /usr/sbin/sendmail

config/conf.pl

@@ -402,6 +402,7 @@ while ( ( $command ne "q" ) && ( $command ne "Q" ) ) {
           if ( lc($useSendmail) eq 'true' ) {
             print $WHT . "Sendmail" . $NRM . "\n--------\n";
             print "4.   Sendmail Path         : $WHT$sendmail_path$NRM\n";
+            print "5.   Suppress SM header    : $WHT$skip_SM_header$NRM\n";
             print "\n";
           } else {
             print $WHT . "SMTP Settings" . $NRM . "\n-------------\n";

config/config_default.php

@@ -101,6 +101,17 @@ $useSendmail = false;
 $smtpServerAddress = 'localhost';
 $smtpPort = 25;
 
+/**
+ * Option can be used to disable Received: headers added by squirrelmail.
+ * This can increase user's privacy and solve problems with spam filters
+ * that increase spam marks for dynamic dialup addresses.
+ *
+ * If admin enables this setting, system should have some logging facility 
+ * or other tools to control users. SquirrelMail's Received: header provides 
+ * information, that can't be forged by webmail user.
+ */
+$skip_SM_header = false;
+
 /**
  * Program that should be used when sending email. SquirrelMail expects that
  * this program will follow options used by original sendmail