diff --git a/kobo/client/__init__.py b/kobo/client/__init__.py
index dce65778..9b47b4f1 100644
--- a/kobo/client/__init__.py
+++ b/kobo/client/__init__.py
@@ -470,6 +470,10 @@ def upload_file(self, file_name, target_dir):
         checksum = sum.hexdigest().lower()
 
         fsize = os.path.getsize(file_name)
+        # use str only for large uploads to not break compatibility with older hubs
+        if fsize > xmlrpclib.MAXINT:
+            fsize = str(fsize)
+
         upload_id, upload_key = self.upload.register_upload(os.path.basename(file_name), checksum, fsize, target_dir)
 
         secure = (scheme == "https")
diff --git a/kobo/django/upload/xmlrpc.py b/kobo/django/upload/xmlrpc.py
index 39a55e07..fdf54a4d 100644
--- a/kobo/django/upload/xmlrpc.py
+++ b/kobo/django/upload/xmlrpc.py
@@ -27,7 +27,8 @@ def register_upload(request, name, checksum, size, target_dir):
     upload.owner = request.user
     upload.name = name
     upload.checksum = checksum.lower()
-    upload.size = size
+    # size may be sent as a string to workaround the xmlrpc.client.MAXINT limit
+    upload.size = int(size)
     upload.target_dir = target_dir
     upload.save()
     return (upload.id, upload.upload_key)