diff --git a/tablib/formats/_xls.py b/tablib/formats/_xls.py
index 0e989a7..08265b0 100644
--- a/tablib/formats/_xls.py
+++ b/tablib/formats/_xls.py
@@ -65,7 +65,11 @@ def dset_sheet(dataset, ws):
 
 			# wrap the rest
 			else:
-				if '\n' in col:
+				try:
+					pass
+				except Exception, e:
+					raise e
+				if (col is None) or ('\n' in col):
 					ws.write(i, j, col, wrap)
 				else:
 					ws.write(i, j, col)