diff --git a/poky/scripts/lib/devtool/sdk.py b/poky/scripts/lib/devtool/sdk.py
index 3aa42a1..ae3fc4c 100644
--- a/poky/scripts/lib/devtool/sdk.py
+++ b/poky/scripts/lib/devtool/sdk.py
@@ -207,7 +207,7 @@
         if not sstate_mirrors:
             with open(os.path.join(conf_dir, 'site.conf'), 'a') as f:
                 f.write('SCONF_VERSION = "%s"\n' % site_conf_version)
-                f.write('SSTATE_MIRRORS_append = " file://.* %s/sstate-cache/PATH \\n "\n' % updateserver)
+                f.write('SSTATE_MIRRORS:append = " file://.* %s/sstate-cache/PATH \\n "\n' % updateserver)
     finally:
         shutil.rmtree(tmpsdk_dir)