Exchange 2010 OWA access from Domain Joined verses non-domain joined

I have a client that currently uses messageware but we would like to remove this requirement. The function that we need to replace and find a solution for using Exchange 2010 is that currently, messageware scans the user's registry that is accessing OWA and tries to locate a entry that identifies the computer as domain joined. This registry setting is distributed to all domain joined workstations using Group Policy. This allows the organization to give different access to company owned computers that are domain joined, and non company owned computers are restricted. Specifically, only the domain joined PCs are allowed to have full access to download attachments. These machines are really not restricted at all. The non-domain joined however are restricted in many ways, caching, attachments and so on... Is there any inherent way I can duplicate this with Exchange 2010 OWA mailbox policies and segmentation? I cannot find anything based on the couple of hours I have spent searching the web...