Afterfter a long series of testing and support calls, Sonicwall produced a 'hotfixed' firmware that seems to fix this issue by adding a check box in the interface configuration to allow duplicate MAC addresses for devices that have multiple IP addresses on a single interface. So far this has proved to resolve the issue.
Hotfix # 142099
No word yet on if this will be released into the next production firmware but the tracking ID for this is the same as the hotfix # and should be referenced in release notes.
I had previously answered this but the answer was deleted...
Update: This hotfix is now in the latest Firmware.