diff -NaurP auth-ldap-2.0.3/aclocal.m4 auth-ldap-2.0.3.gcc47/aclocal.m4
--- auth-ldap-2.0.3/aclocal.m4	2006-09-12 15:44:13.000000000 -0500
+++ auth-ldap-2.0.3.gcc47/aclocal.m4	2012-08-12 18:58:57.568425790 -0500
@@ -156,11 +156,20 @@
 			AC_LINK_IFELSE([
 					AC_LANG_PROGRAM([
 							#include <objc/objc.h>
+							#ifdef __GNU_LIBOBJC__
+							#include <objc/runtime.h>
+							#else
 							#include <objc/objc-api.h>
+							#endif
 						], [
+							#ifdef __GNU_LIBOBJC__
+							Class class = objc_lookUpClass("Object");
+							puts(class_getName(class));
+							#else
 							id class = objc_lookup_class("Object");
 							id obj = @<:@class alloc@:>@;
 							puts(@<:@obj name@:>@);
+							#endif
 						])
 					], [
 						od_cv_objc_runtime_gnu="yes"
diff -NaurP auth-ldap-2.0.3/configure auth-ldap-2.0.3.gcc47/configure
--- auth-ldap-2.0.3/configure	2007-03-22 14:32:56.000000000 -0600
+++ auth-ldap-2.0.3.gcc47/configure	2012-08-12 19:01:58.666161758 -0500
@@ -6459,15 +6459,24 @@
 /* end confdefs.h.  */
 
 							#include <objc/objc.h>
+							#ifdef __GNU_LIBOBJC__
+							#include <objc/runtime.h>
+							#else
 							#include <objc/objc-api.h>
+							#endif
 
 int
 main ()
 {
 
+							#ifdef __GNU_LIBOBJC__
+							Class class = objc_lookUpClass("Object");
+							puts(class_getName(class));
+							#else
 							id class = objc_lookup_class("Object");
 							id obj = [class alloc];
 							puts([obj name]);
+							#endif
 
   ;
   return 0;