Using:    <IMAddresses use-default="false">       <IMAddress>mail</IMAddress>    </IMAddresses> is unsupported. If you are using this configuration you are in an unsupported configuration and will not be supported by Cisco. The only correct config ...

Unfortunately, there is currently no way of doing  this. 

This feature has not been committed so I can't confirm what its content will be if it ever is committed to a release. Currently, I don't believe there is any plans for it.