Order By When You Have Joined Tables

If I use order by on a query that has two linked tables I keep getting an error:
This is the query
SELECT d.PDetailsID, d.po_id, d.po_uniqid, d.job_id,
d.p_qnty, d.p_desc, d.p_unitp, d.p_units,
d.p_extend, d.p_qos, d.p_grec, d.p_done,
d.cocreq, d.est_id, d.line, d.class,
d.selected, d.itemid, d.category, d.GroupID,
d.p_qosextended, d.late, d.lastsavedby, d.matid,
d.customer, SQLACCESS.tblctpur_d.jobid, d.DTime, d.Notes,
d.DescDetails, h.pur_ddue
FROM SQLACCESS.tblctpur_h as h INNER JOIN
SQLACCESS.tblctpur_d as d ON h.pur_id = d.po_id
ORDER BY d.line

The error is :
The colum prefix d does not match with a table or alias used in the query