diff --git a/Makefile.am b/Makefile.am
index d40f253..9075bfc 100644
--- a/Makefile.am
+++ b/Makefile.am
@@ -24,7 +24,7 @@
 		parser.c tree.c hash.c list.c xmlIO.c xmlmemory.c uri.c  \
 		valid.c xlink.c HTMLparser.c HTMLtree.c debugXML.c xpath.c  \
 		xpointer.c xinclude.c nanohttp.c nanoftp.c DOCBparser.c \
-		catalog.c globals.c threads.c c14n.c \
+		catalog.c globals.c threads.c c14n.c xmlstring.c \
 		xmlregexp.c xmlschemas.c xmlschemastypes.c xmlunicode.c \
 		triostr.c trio.c xmlreader.c relaxng.c dict.c SAX2.c \
 		xmlwriter.c legacy.c chvalid.c pattern.c
@@ -33,7 +33,7 @@
 		parser.c tree.c hash.c list.c xmlIO.c xmlmemory.c uri.c  \
 		valid.c xlink.c HTMLparser.c HTMLtree.c debugXML.c xpath.c  \
 		xpointer.c xinclude.c nanohttp.c nanoftp.c DOCBparser.c \
-		catalog.c globals.c threads.c c14n.c \
+		catalog.c globals.c threads.c c14n.c xmlstring.c \
 		xmlregexp.c xmlschemas.c xmlschemastypes.c xmlunicode.c \
 		xmlreader.c relaxng.c dict.c SAX2.c \
 		xmlwriter.c legacy.c chvalid.c pattern.c