diff --git a/ChangeLog b/ChangeLog
index 0eb4bca76..77a03efe9 100644
--- a/ChangeLog
+++ b/ChangeLog
@@ -4,6 +4,8 @@
 	* Source/GSSocketStream.m:
 	Avoid unnecessary memory allocation.
 	Use weak pointers to break finalisation cycles.
+	* Source/NSZone.m: Use GC debug unless built with 'debug=no'
+	Allocate memory ignoring pointers into the allocated data.
 
 2009-03-21  Richard Frith-Macdonald <rfm@gnu.org>
 
diff --git a/Source/NSZone.m b/Source/NSZone.m
index 13732f298..d71bda6e5 100644
--- a/Source/NSZone.m
+++ b/Source/NSZone.m
@@ -1753,6 +1753,10 @@ NSReallocateCollectable(void *ptr, NSUInteger size, NSUInteger options)
 }
 #else
 
+#if	defined(DEBUG)
+#define	GC_DEBUG	1
+#endif
+
 #include <gc.h>
 
 /*
@@ -1784,7 +1788,7 @@ NSAllocateCollectable(NSUInteger size, NSUInteger options)
 	}
       else
 	{
-          ptr = (void*)GC_MALLOC(size);
+          ptr = (void*)GC_MALLOC_IGNORE_OFF_PAGE(size);
 	  memset(ptr, '\0', size);
 	}
     }
@@ -1796,7 +1800,7 @@ NSAllocateCollectable(NSUInteger size, NSUInteger options)
 	}
       else
 	{
-	  ptr = (void*)GC_MALLOC_ATOMIC(size);
+	  ptr = (void*)GC_MALLOC_ATOMIC_IGNORE_OFF_PAGE(size);
 	  memset(ptr, '\0', size);
 	}
     }