diff --git a/libtiff/libtiff.def b/libtiff/libtiff.def
index a9f86645..d074a10f 100644
--- a/libtiff/libtiff.def
+++ b/libtiff/libtiff.def
@@ -137,3 +137,5 @@ EXPORTS TIFFOpen
  	TIFFAccessTagMethods
  	TIFFGetClientInfo
  	TIFFSetClientInfo
+	TIFFSwabLong8
+	TIFFSwabArrayOfLong8