Clarified copyright notice

src/interfaces/ecpg/compatlib/informix.c

-/* $PostgreSQL: pgsql/src/interfaces/ecpg/compatlib/informix.c,v 1.43 2006/06/21 10:24:40 meskes Exp $ */
+/* $PostgreSQL: pgsql/src/interfaces/ecpg/compatlib/informix.c,v 1.44 2006/06/23 14:50:01 meskes Exp $ */
 
 #include <stdlib.h>
 #include <string.h>
@@ -672,6 +672,7 @@ intoasc(interval * i, char *str)
 	begin				 : Wed Apr 2 2003
 	copyright			 : (C) 2003 by Carsten Wolff
 	email				 : carsten.wolff@credativ.de
+	Contributed under the PostgreSQL License by credativ GmbH
  ***************************************************************************/
 
 static struct