microphat:
While you're waiting for a response, you can always try dumping the config from your C-10 onto your new C-150. In my experience the IronPort C-series will read a config from another appliance just fine running an older release as long as it's in the same point release. (meaning 6.1.x) I wouldn't try going from a newer firmware down to an older firmware though.
Before I would attempt this, I would download the config from your C-10 and the config from your C-150 and see what the differences are (windif or Notepad++ can do this for you. While there will be quite a bit of differences like IP settings, message filters, general config and the like, you can also see configuration file format changes.
The configuration file format is pretty clean and it's usually very obvious when there is a major change in the format.
Additionally, AsyncOS is pretty good in telling you the configuration file has errors upon import, so you shouldn't end up with a hosed system.
However, it's always best to use configs from the same AsyncOS build.
