1 files changed, 3 insertions, 2 deletions
diff --git a/Swiften/Avatars/AvatarProvider.h b/Swiften/Avatars/AvatarProvider.h
index d2d408e..3606376 100644
--- a/Swiften/Avatars/AvatarProvider.h
+++ b/Swiften/Avatars/AvatarProvider.h
@@ -9,4 +9,5 @@
 #include <string>
 
+#include <Swiften/Base/API.h>
 #include <Swiften/Base/boost_bsignals.h>
 
@@ -14,9 +15,9 @@ namespace Swift {
 	class JID;
 
-	class AvatarProvider {
+	class SWIFTEN_API AvatarProvider {
 		public:
 			virtual ~AvatarProvider();
 
-			virtual std::string getAvatarHash(const JID&) const = 0;
+			virtual boost::optional<std::string> getAvatarHash(const JID&) const = 0;
 
 			boost::signal<void (const JID&)> onAvatarChanged;