How do I get automatic ring volume control?

[master4g]

I have the Sprint Touch Diamond and before this phone, I used to have the Motorola Q9c which was a smartphone. On that phone one of the ring profiles said "automatic" and i think the way it worked was that if there was a apointment or meeting scheduled in the calendar then the volume would automaticly be silent or vibrate, otherwise it would ring.

On my touch diamond, I don't see any setting like that. What I would like is have a setting to have the phone automaticly go to vibrate for several minutes throughout the day, for example, for 10 minutes when im having dinner, etc

It would be OK for me to just put dinner , lunch etc in the calender to shut my phone up during thesee times, but I would prefer not clogging up my calendar with these things every day, so if there is a software which allows you to set these times without putting them on the calendar would be great

Any setting or application???????? Thanks