diff --git a/src/oneprovision/lib/provision/provision.rb b/src/oneprovision/lib/provision/provision.rb
index c1a7a07cc6..c322cec824 100644
--- a/src/oneprovision/lib/provision/provision.rb
+++ b/src/oneprovision/lib/provision/provision.rb
@@ -13,6 +13,7 @@
 #--------------------------------------------------------------------------- #
 
 require 'opennebula/document_json'
+require 'opennebula/wait_ext'
 
 module OneProvision