Setting iCal calendar to show as always busy/unavailable on Exchange

[coiner]

I have a user who would like his calendar (which is synced on exchange) to show that he is always unavailable. So, for example, let's say he creates several meetings and shares them with the individuals he is meeting with. They would be able to see his meeting with them but all other times on his calendar would show as "busy" or "unavailable." Or if someone he hasn't scheduled a meeting with looks at his exchange calendar, it will just show all times as unavailable instead of showing the individual blocks of time that he has set up as meetings. Is there a way to do this?