Index: program/include/main.inc
===================================================================
--- program/include/main.inc	(revision 8e5ed7be9e754dfca0278653002ec75f9199d8a9)
+++ program/include/main.inc	(revision d7a5dfa26abe21aa9216fe862225baa2b5caca3e)
@@ -1587,5 +1587,5 @@
   $regexp = '&^(?:
 	("\s*(?:[^"\f\n\r\t\v\b\s]+\s*)+")| 			 	#1 quoted name
-	([-\w!\#\$%\&\'*+~/^`|{}]+(?:\.[-\w!\#\$%\&\'*+~/^`|{}]+)*)) 	#2 OR dot-atom
+	([-\w!\#\$%\&\'*+~/^`|{}=]+(?:\.[-\w!\#\$%\&\'*+~/^`|{}=]+)*)) 	#2 OR dot-atom (RFC5322)
 	$&xi';