diff -Nurd -x'*~' libdap-3.5.2.orig/gl/putenv.c libdap-3.5.2/gl/putenv.c
--- libdap-3.5.2.orig/gl/putenv.c	2005-08-08 18:11:06.000000000 -0400
+++ libdap-3.5.2/gl/putenv.c	2007-08-06 13:19:58.000000000 -0400
@@ -46,7 +46,12 @@
 #if HAVE_GNU_LD
 # define environ __environ
 #else
-extern char **environ;
+#ifdef __APPLE__
+#include <crt_externs.h>
+#define environ (*_NSGetEnviron())
+#else
+ extern char **environ;
+#endif
 #endif
 
 #if _LIBC