I can confirm that the changes i suggested in my last post DO work in a LIVE environment on worldpay. I've had 3 orders come in in the last hour with no problems.
Just for the record i'm using Worldpay module 2.10 on 2 versions of zencart, 1.3.7.1 and 1.3.8a
And responding to a previous posting version 2.10 will show version 2.09 in your admin.
As always backup everything and use in test environment first then go live. Use at your own risk.
Also as to if it is dynamic or static according to worldpay this module should be static
This module sends the same params each time.Static Signatures (recommended method of generating MD5 signatures)
Merchants, who encrypt the same transaction parameters for every transaction, must now specify their signatureFields value in their Installation Settings located in the Merchant Administration Interface. Please note that this replaces the need to send the signatureFields parameter in your order details submission.
Cheers
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