diff --git a/omeroweb/settings.py b/omeroweb/settings.py
index c19fe57c59..2f73e76821 100755
--- a/omeroweb/settings.py
+++ b/omeroweb/settings.py
@@ -40,8 +40,8 @@
 import random
 import string
 from builtins import str as text
+import portalocker
 
-from omero_ext import portalocker
 from omero.util.concurrency import get_event
 from omeroweb.utils import sort_properties_to_tuple
 from omeroweb.connector import Server
diff --git a/setup.py b/setup.py
index 2a3fd4a34c..b119f6c9a6 100755
--- a/setup.py
+++ b/setup.py
@@ -61,6 +61,7 @@ def read(fname):
         "gunicorn>=19.3",
         "omero-marshal>=0.7.0",
         "Pillow",
+        "portalocker",
     ],
     include_package_data=True,
     tests_require=["pytest"],