Index: wp-includes/pluggable.php
===================================================================
--- wp-includes/pluggable.php	(revision 19998)
+++ wp-includes/pluggable.php	(working copy)
@@ -432,7 +432,13 @@
 	// Send!
 	try {
 		$phpmailer->Send();
-	} catch ( phpmailerException $e ) {
+	} catch ( phpmailerException $e ) {		
+		if ( WP_DEBUG ) 
+ 			error_log( sprintf('Cannot send mail. Recipient: %s; Subject: %s -- Error: %s', $to, $subject, $e->getCode(), $e->getMessage() ) ); 
+		
+		$mail_error_data = compact( $to, $subject, $message, $headers, $attachments );
+ 		do_action( 'wp_mail_fail', new WP_Error( $e->getCode(), $e->getMessage(), $mail_error_data ) );
+		
 		return false;
 	}