@@ -5,10 +5,11 @@
 HTML_OUTPUT = .
 GENERATE_LATEX = NO
 HIDE_UNDOC_CLASSES = YES
 HIDE_UNDOC_MEMBERS = YES
 PREDEFINED = OF_HAVE_PROPERTIES		\
+	     OF_HAVE_OPTIONAL_PROTOCOLS	\
 	     OF_HAVE_BLOCKS		\
 	     OF_HAVE_THREADS		\
 	     OF_SENTINEL		\
 	     OF_RETURNS_RETAINED	\
 	     OF_RETURNS_NOT_RETAINED	\