diff --git a/src/Makefile b/src/Makefile
index d3a3d6561..6c060c4d3 100644
--- a/src/Makefile
+++ b/src/Makefile
@@ -63,7 +63,7 @@ news.o:         news.c      $(INCLUDES)
 nickserv.o:     nickserv.c  $(INCLUDES)
 operserv.o:     operserv.c  $(INCLUDES)
 process.o:      process.c   $(INCLUDES)
-protocol.o:     protocol.c  $(INCLUDES)
+protocol.o:     protocol.cpp  $(INCLUDES)
 send.o:         send.c      $(INCLUDES)
 servers.o:      servers.c   $(INCLUDES)
 sessions.o:     sessions.c  $(INCLUDES)