fix for issue 5548. Deprecated old classes and created subclasses.
diff --git a/src/objective-c/ProtoRPC/ProtoService.m b/src/objective-c/ProtoRPC/ProtoService.m
index fccc6aa..597c3cf 100644
--- a/src/objective-c/ProtoRPC/ProtoService.m
+++ b/src/objective-c/ProtoRPC/ProtoService.m
@@ -79,3 +79,7 @@
                      responsesWriteable:responsesWriteable];
 }
 @end
+
+@implementation GRPCProtoService
+
+@end