Index: includes/common.inc
===================================================================
RCS file: /cvs/drupal/drupal/includes/common.inc,v
retrieving revision 1.756.2.72
diff -u -r1.756.2.72 common.inc
--- includes/common.inc	6 Oct 2009 12:03:11 -0000	1.756.2.72
+++ includes/common.inc	6 Oct 2009 15:44:54 -0000
@@ -939,14 +939,15 @@
  */
 
 /**
- * Verify the syntax of the given e-mail address.
+ * Verifies the syntax of the given e-mail address.
  *
- * Empty e-mail addresses are allowed. See RFC 2822 for details.
+ * See RFC 2822 for details.
  *
  * @param $mail
  *   A string containing an e-mail address.
  * @return
- *   TRUE if the address is in a valid format.
+ *   1 if the email address is valid, 0 if it is invalid or empty, and FALSE if
+ *   there is an input error (such as passing in an array instead of a string).
  */
 function valid_email_address($mail) {
   $user = '[a-zA-Z0-9_\-\.\+\^!#\$%&*+\/\=\?\`\|\{\}~\']+';