diff --git a/Makefile.defs b/Makefile.defs
index 8b667a94ee8..ba2ae19b441 100644
--- a/Makefile.defs
+++ b/Makefile.defs
@@ -97,7 +97,7 @@ INSTALL_FLAVOUR=$(FLAVOUR)
 VERSION = 4
 PATCHLEVEL = 4
 SUBLEVEL =  0
-EXTRAVERSION = -dev5
+EXTRAVERSION = -dev6
 
 # memory manager switcher
 # 0 - f_malloc (fast malloc)