--- Makefile.am.orig	2015-09-11 14:02:04.245280051 +0100
+++ Makefile.am	2016-01-01 14:00:49.857225492 +0000
@@ -652,7 +652,7 @@
 
 stamps/netx-docs.stamp:
 if ENABLE_DOCS
-	$(SYSTEM_JDK_DIR)/bin/javadoc $(JAVADOC_MEM_OPTS) $(	_OPTS) \
+	$(SYSTEM_JDK_DIR)/bin/javadoc $(JAVADOC_MEM_OPTS) $(JAVADOC_OPTS) \
 	 -d ${abs_top_builddir}/docs/netx -sourcepath $(NETX_SRCDIR) \
 	 -doctitle 'IcedTea-Web: NetX API Specification' \
 	 -windowtitle 'IcedTea-Web: NetX ' \