diff --git a/rattail_corepos/corepos/importing/db/exporters/catapult_inventory.py b/rattail_corepos/corepos/importing/db/exporters/catapult_inventory.py
index 090e16d..3965c42 100644
--- a/rattail_corepos/corepos/importing/db/exporters/catapult_inventory.py
+++ b/rattail_corepos/corepos/importing/db/exporters/catapult_inventory.py
@@ -119,7 +119,7 @@ class InventoryItemImporter(FromCore, catapult_importing.model.InventoryItemImpo
         super(InventoryItemImporter, self).setup()
 
         # this is used for sorting, when a value has no date
-        self.old_date = datetime.date(1900, 1, 1)
+        self.old_datetime = datetime.datetime(1900, 1, 1)
 
         self.ignored_upcs = self.config.getlist(
             'corepos', 'exporting.catapult_inventory.ignored_upcs')
@@ -345,7 +345,7 @@ class InventoryItemImporter(FromCore, catapult_importing.model.InventoryItemImpo
                            product.upc, len(vendor_items), product)
 
                     # sort the list so most recently modified is first
-                    vendor_items.sort(key=lambda item: item.modified or self.old_date,
+                    vendor_items.sort(key=lambda item: item.modified or self.old_datetime,
                                       reverse=True)
 
             # use the "first" vendor item available