diff --git a/blacklist-py3.txt b/blacklist-py3.txt
index ad96f260f7..ba62333b11 100644
--- a/blacklist-py3.txt
+++ b/blacklist-py3.txt
@@ -1,6 +1,4 @@
 # Use a blacklist of tests known to fail on Python 3, until
 # all unit tests will pass on Python 3.
-guestagent.test_cassandra_manager
-guestagent.test_mongodb_manager
 guestagent.test_operating_system
 guestagent.test_volume
diff --git a/trove/common/pagination.py b/trove/common/pagination.py
index c1bc9ef56c..7e45d86fb0 100644
--- a/trove/common/pagination.py
+++ b/trove/common/pagination.py
@@ -37,6 +37,8 @@ def paginate_list(li, limit=None, marker=None, include_marker=False,
     """
     sli = sorted(li, key=key)
     index = [key(item) for item in sli]
+    if marker is None:
+        marker = ''
     if include_marker:
         pos = bisect.bisect_left(index, marker)
     else: