Index: src/OFApplication.h
==================================================================
--- src/OFApplication.h
+++ src/OFApplication.h
@@ -37,10 +37,13 @@
  * This method is called when the application was initialized and is running
  * now.
  */
 - (void)applicationDidFinishLaunching;
 
+#ifdef OF_HAVE_OPTIONAL_PROTOCOLS
+@optional
+#endif
 /**
  * This method is called when the application will terminate.
  */
 - (void)applicationWillTerminate;
 @end

Index: src/OFStreamObserver.h
==================================================================
--- src/OFStreamObserver.h
+++ src/OFStreamObserver.h
@@ -37,11 +37,13 @@
 /**
  * \brief A protocol that needs to be implemented by delegates for
  *	  OFStreamObserver.
  */
 @protocol OFStreamObserverDelegate
-
+#ifdef OF_HAVE_OPTIONAL_PROTOCOLS
+@optional
+#endif
 /**
  * This callback is called when a stream did get ready for reading.
  *
  * \param stream The stream which did become ready for reading
  */

Index: src/OFXMLElementBuilder.h
==================================================================
--- src/OFXMLElementBuilder.h
+++ src/OFXMLElementBuilder.h
@@ -36,10 +36,13 @@
  * \param elem The OFXMLElement the OFXMLElementBuilder built
  */
 - (void)elementBuilder: (OFXMLElementBuilder*)builder
        didBuildElement: (OFXMLElement*)elem;
 
+#ifdef OF_HAVE_OPTIONAL_PROTOCOLS
+@optional
+#endif
 /**
  * This callback is called when the OFXMLElementBuilder gets a close tag which
  * does not belong there.
  *
  * Most likely, the OFXMLElementBuilder was used to build XML only of a child

Index: src/OFXMLParser.h
==================================================================
--- src/OFXMLParser.h
+++ src/OFXMLParser.h
@@ -38,10 +38,13 @@
 
 /**
  * \brief A protocol that needs to be implemented by delegates for OFXMLParser.
  */
 @protocol OFXMLParserDelegate
+#ifdef OF_HAVE_OPTIONAL_PROTOCOLS
+@optional
+#endif
 /**
  * This callback is called when the XML parser found processing instructions.
  *
  * \param parser The parser which found processing instructions
  * \param pi The processing instructions