diff --git a/modules/zlib/macbuild/zLib.Prefix b/modules/zlib/macbuild/zLib.Prefix
index 3ef273891da..6e3569e1946 100644
--- a/modules/zlib/macbuild/zLib.Prefix
+++ b/modules/zlib/macbuild/zLib.Prefix
@@ -16,10 +16,11 @@
  * Reserved.
  */
 //
-//	NSPR.Prefix
+//	zlib.Prefix
 //
-// Global prefix file for the debug NSPR project.
+// Global prefix file for the zlib project.
 //
 //
 
-#include "zLibConfig.h"
\ No newline at end of file
+#include "MacPrefix.h"
+#include "zLibConfig.h"
diff --git a/modules/zlib/macbuild/zLibConfig.h b/modules/zlib/macbuild/zLibConfig.h
index f1f237ee0e4..0a3b97ff5ad 100644
--- a/modules/zlib/macbuild/zLibConfig.h
+++ b/modules/zlib/macbuild/zLibConfig.h
@@ -15,8 +15,9 @@
  * Copyright (C) 1998 Netscape Communications Corporation.  All Rights
  * Reserved.
  */
-#define EDITOR 1
-//#define JAVA 1
-#define Z_PREFIX 
-#include "NSCrossProductDefines.h"
-#include "IDE_Options.h"
+
+/* Nothing to do here. Define zlib specific stuff here if necessary */
+
+/* I don't think we need this any more. If we do, it needs to be
+	globally defined. */
+//#define Z_PREFIX 
diff --git a/modules/zlib/macbuild/zLibDebug.Prefix b/modules/zlib/macbuild/zLibDebug.Prefix
index d6911f50455..84db2b612b2 100644
--- a/modules/zlib/macbuild/zLibDebug.Prefix
+++ b/modules/zlib/macbuild/zLibDebug.Prefix
@@ -16,13 +16,12 @@
  * Reserved.
  */
 //
-//	NSPR.Prefix
+//	zlibDebug.Prefix
 //
-// Global prefix file for the debug NSPR project.
+// Global prefix file for the debug zlib project.
 //
 //
 
 
-#define DEBUG 1
-#define DEVELOPER_DEBUG 1
-#include "zLibConfig.h"
\ No newline at end of file
+#include "MacPrefix_debug.h"
+#include "zLibConfig.h"
diff --git a/modules/zlib/macbuild/zlib.mcp b/modules/zlib/macbuild/zlib.mcp
index f5f6b44f2fb..a9bee397237 100644
Binary files a/modules/zlib/macbuild/zlib.mcp and b/modules/zlib/macbuild/zlib.mcp differ