diff --git a/modules/zlib/src/zlib.def b/modules/zlib/src/zlib.def
index a47cbc10caea..30d83f18f2f2 100644
--- a/modules/zlib/src/zlib.def
+++ b/modules/zlib/src/zlib.def
@@ -3,58 +3,58 @@ LIBRARY
 
 EXPORTS
 ; basic functions
-    zlibVersion
-    deflate
-    deflateEnd
-    inflate
-    inflateEnd
+    MOZ_Z_zlibVersion
+    MOZ_Z_deflate
+    MOZ_Z_deflateEnd
+    MOZ_Z_inflate
+    MOZ_Z_inflateEnd
 ; advanced functions
-    deflateSetDictionary
-    deflateCopy
-    deflateReset
-    deflateParams
-    deflateBound
-    deflatePrime
-    inflateSetDictionary
-    inflateSync
-    inflateCopy
-    inflateReset
-    inflateBack
-    inflateBackEnd
-    zlibCompileFlags
+    MOZ_Z_deflateSetDictionary
+    MOZ_Z_deflateCopy
+    MOZ_Z_deflateReset
+    MOZ_Z_deflateParams
+    MOZ_Z_deflateBound
+    MOZ_Z_deflatePrime
+    MOZ_Z_inflateSetDictionary
+    MOZ_Z_inflateSync
+    MOZ_Z_inflateCopy
+    MOZ_Z_inflateReset
+    MOZ_Z_inflateBack
+    MOZ_Z_inflateBackEnd
+    MOZ_Z_zlibCompileFlags
 ; utility functions
-    compress
-    compress2
-    compressBound
-    uncompress
-    gzopen
-    gzdopen
-    gzsetparams
-    gzread
-    gzwrite
-    gzprintf
-    gzputs
-    gzgets
-    gzputc
-    gzgetc
-    gzungetc
-    gzflush
-    gzseek
-    gzrewind
-    gztell
-    gzeof
-    gzclose
-    gzerror
-    gzclearerr
+    MOZ_Z_compress
+    MOZ_Z_compress2
+    MOZ_Z_compressBound
+    MOZ_Z_uncompress
+    MOZ_Z_gzopen
+    MOZ_Z_gzdopen
+    MOZ_Z_gzsetparams
+    MOZ_Z_gzread
+    MOZ_Z_gzwrite
+    MOZ_Z_gzprintf
+    MOZ_Z_gzputs
+    MOZ_Z_gzgets
+    MOZ_Z_gzputc
+    MOZ_Z_gzgetc
+    MOZ_Z_gzungetc
+    MOZ_Z_gzflush
+    MOZ_Z_gzseek
+    MOZ_Z_gzrewind
+    MOZ_Z_gztell
+    MOZ_Z_gzeof
+    MOZ_Z_gzclose
+    MOZ_Z_gzerror
+    MOZ_Z_gzclearerr
 ; checksum functions
-    adler32
-    crc32
+    MOZ_Z_adler32
+    MOZ_Z_crc32
 ; various hacks, don't look :)
-    deflateInit_
-    deflateInit2_
-    inflateInit_
-    inflateInit2_
-    inflateBackInit_
-    inflateSyncPoint
-    get_crc_table
-    zError
+    MOZ_Z_deflateInit_
+    MOZ_Z_deflateInit2_
+    MOZ_Z_inflateInit_
+    MOZ_Z_inflateInit2_
+    MOZ_Z_inflateBackInit_
+    MOZ_Z_inflateSyncPoint
+    MOZ_Z_get_crc_table
+    MOZ_Z_zError