Dear All,
I've been building a zencart store over the last two weeks, and as our other (actinic) store uses secpay I decided to use it here too.
After scratching around trying to cure the digest (possible fraud attempt) problem I found a really useful page over on oscommerce
try http://forums.oscommerce.com/index.php?showtopic=255409
Worked for me!
All the best,
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