diff --git a/doc/source/conf.py b/doc/source/conf.py
index 1d0fda53893..6b5f9386010 100644
--- a/doc/source/conf.py
+++ b/doc/source/conf.py
@@ -252,3 +252,27 @@ texinfo_documents = [
 
 # How to display URL addresses: 'footnote', 'no', or 'inline'.
 #texinfo_show_urls = 'footnote'
+
+# -- ReadTheDocs.org Settings ------------------------------------------------
+
+class Mock(object):
+    def __init__(self, *args, **kwargs):
+        pass
+
+    def __call__(self, *args, **kwargs):
+        return Mock()
+
+    @classmethod
+    def __getattr__(cls, name):
+        if name in ('__file__', '__path__'):
+            return '/dev/null'
+        elif name[0] == name[0].upper():
+            mockType = type(name, (), {})
+            mockType.__module__ = __name__
+            return mockType
+        else:
+            return Mock()
+
+MOCK_MODULES = ['tables', 'pbs_python', 'DRMAA_python', 'decorator']
+for mod_name in MOCK_MODULES:
+    sys.modules[mod_name] = Mock()