Autocomplete widgets for ubercart orders entity reference fields give fatal error

Not sure if the fix for this lies in the entity reference module or ubercart...

The issue is that autocomplete and autocomplete tag style widget options return a fatal error on ajax calls in response to user input. Specifically, the resulting query has a non sensical WHERE clause - 'WHERE (uc_orders.Order LIKE' - where Order should actually order_id.

See below for full error message.

An AJAX HTTP error occurred.
HTTP Result Code: 500
Debugging information follows.
Path: http://dev.dev/entityreference/autocomplete/single/field_booking_order_r...
StatusText: Service unavailable (with message)
ResponseText: PDOException: SQLSTATE[42S22]: Column not found: 1054 Unknown column 'uc_orders.Order' in 'where clause': SELECT uc_orders.order_id AS entity_id, :entity_type AS entity_type, NULL AS revision_id, :bundle AS bundle
FROM
{uc_orders} uc_orders
WHERE (uc_orders.Order LIKE :db_condition_placeholder_0 ESCAPE '\\')
LIMIT 10 OFFSET 0; Array
(
[:db_condition_placeholder_0] => %5%
[:entity_type] => uc_order
[:bundle] => uc_order
)
in EntityFieldQuery->execute() (line 1144 of /portal/docroot/includes/entity.inc).