diff --git a/gns3server/version.py b/gns3server/version.py
index 6570771f..3a76b51c 100644
--- a/gns3server/version.py
+++ b/gns3server/version.py
@@ -23,5 +23,5 @@
 # or negative for a release candidate or beta (after the base version
 # number has been incremented)
 
-__version__ = "1.5.0"
-__version_info__ = (1, 5, 0, 0)
+__version__ = "1.5.1dev1"
+__version_info__ = (1, 5, 1, -99)