Mulching citrus with coffee grounds

I've been mulching my citrus with coffee grounds to acidify the soil. I'd like to hear other people's experiences with doing this. Does it work well? What's a good complement to add to the coffee grounds?

The following thread was started by Axel on May 07, 2008 at 8:14 pm PST

I follow an old family tradition of mulching with coffee grounds and scattering crushed eggshells. Perhaps there's no science behind it but the trees are very productive and disease-free.

The above followup was added by Merbert on May 08, 2008 at 0:14 am PST.