That would be the software level of emanager you are reading. The feature will be greyed out if the phone system software does not support a feature.

I have never seen that COS NOT greyed out on any system I have connected to. I have seen that COS in eManager for some time. I don't know if they ever implemented it or if they did at one time then removed it. I just checked software level from about a year ago and it was grey also. I can check a more recent version when I get a chance.