diff --git a/liquid_tags/notebook.py b/liquid_tags/notebook.py
index 954efaf..0728999 100644
--- a/liquid_tags/notebook.py
+++ b/liquid_tags/notebook.py
@@ -49,7 +49,7 @@ import os
 from .mdx_liquid_tags import LiquidTags
 
 import IPython
-if IPython.__version__.split('.')[0] != 1:
+if IPython.__version__.split('.')[0] != '1':
     raise ValueError("IPython version 1.0+ required for notebook tag")
 
 from IPython import nbconvert