diff -rU3 cacert.orig/includes/general.php cacert/includes/general.php
--- cacert.orig/includes/general.php	2007-07-13 19:39:57.000000000 +0200
+++ cacert/includes/general.php	2007-07-17 14:10:33.000000000 +0200
@@ -644,7 +644,7 @@
 						$line = fgets($fp, 4096);
 					if(substr($line, 0, 3) != "250")
 						continue;
-					fputs($fp, "MAIL FROM: <returns@cacert.org>\r\n");
+					fputs($fp, "MAIL FROM: <>\r\n");
 					$line = fgets($fp, 4096);
 
 					if(substr($line, 0, 3) != "250")