diff --git a/unix/vncviewer/Makefile.am b/unix/vncviewer/Makefile.am
index 2b1e966..cfbe430 100644
--- a/unix/vncviewer/Makefile.am
+++ b/unix/vncviewer/Makefile.am
@@ -18,4 +18,8 @@
 	$(top_builddir)/common/rdr/librdr.la \
 	@X_PRE_LIBS@ @X_LIBS@ -lXext -lX11 @X_EXTRA_LIBS@ @GNUTLS_LIBS@ # @LIBINTL@
 
+if INCLUDED_ZLIB
+vncviewer_LDADD += $(top_builddir)/common/zlib/libz.la
+endif
+
 EXTRA_DIST = vncviewer.man
diff --git a/unix/x0vncserver/Makefile.am b/unix/x0vncserver/Makefile.am
index 80a27b3..b37537c 100644
--- a/unix/x0vncserver/Makefile.am
+++ b/unix/x0vncserver/Makefile.am
@@ -21,4 +21,8 @@
 	$(top_builddir)/unix/tx/libtx.la @INET_LIB@ @X_PRE_LIBS@ @X_LIBS@ \
 	@XTEST_LIB@ -lXext -lX11 @X_EXTRA_LIBS@ @GNUTLS_LIBS@
 
+if INCLUDED_ZLIB
+x0vncserver_LDADD += $(top_builddir)/common/zlib/libz.la
+endif
+
 EXTRA_DIST = x0vncserver.man