[Exim] MySQL query

Hi All,

How do you supply a header value to a MySQL query??
I am trying to complete the following:

${lookup mysql {select autoid from external where address =
'${lc:$h_from:}'}}

It doesn't appear the from value in the header is being substituted in.

Regards,
Dougal McWhinney
Acting IT/Control Systems Supervisor.
Queensland Magnesia Pty Ltd
246 Boundary Rd, Parkhurst Qld
Mail: PO Box 5798, Central Queensland Mail Centre. QLD 4702
e-mail: dmcwhinney@???
Phone: +61 7 4920 0236
Mobile: 0438 200 526
Fax: +61 7 4936 1380

"Never argue with an idiot. They drag you down to their level, then beat
you with experience."