diff -rupN a/dat/common/dat_strerror.c b/dat/common/dat_strerror.c
--- a/dat/common/dat_strerror.c	2012-01-13 18:55:59.000000000 +0000
+++ b/dat/common/dat_strerror.c	2013-09-09 09:12:05.449792410 +0000
@@ -37,6 +37,8 @@
  * $Id: dat_strerror.c,v 1.10 2005/03/24 05:58:28 jlentini Exp $
  **********************************************************************/
 
+#include <stdlib.h>
+
 #ifdef __KDAPL__
 #include <dat2/kdat.h>
 #else /*__UDAPL__*/