diff --git a/pdfio1.def b/pdfio1.def
index 069095d..223d206 100644
--- a/pdfio1.def
+++ b/pdfio1.def
@@ -51,6 +51,9 @@ _pdfioFileRead
 _pdfioFileSeek
 _pdfioFileTell
 _pdfioFileWrite
+_pdfioLZWCreate
+_pdfioLZWDelete
+_pdfioLZWInflate
 _pdfioObjDelete
 _pdfioObjGetExtension
 _pdfioObjLoad