What version are you running?
Within the Domain Signature settings, select the domain under mapping and enable allow users to override this mapping. This will allow the users to select what domain signature they wanted. The down side is the users can change the signature and the default will the the user signature. You can change the default signature to the domain signature but each user settings will required to be manual changed by selecting signature under account settings and changing the mapping to domain signature. The signature you select from the domain settings will then by default but the additional ones will be available also.
I would suggest making a feature request to be able to map multiple domain signature that users cannot override and still have the option to choose which domain signature they would like to use. Currently disabling allow users to override only allows the default to be used.
Mark Milton
Pro Tech North
Web: www.protech-north.co.uk
Email: mark.milton@protech-north.co.uk
Tel: +44 (0)1261 838282
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