The soil and compost forum is full of compost junkies...someone there can probably sort your question out if no one here does.

http://forums2.gardenweb.com/forums/soil/

Here is a link that might be useful: GardenWeb Soil and Compost Forum

*facepalm* Go figure. And I bet it was in plain view too. :) Ah well. Thank you sir or madam, I'll be scooting along now.

I searched, in vain, witchapparatus, for your repost chez the compostier forum.

Your question is worthy of deep pondering.

I assume you've eliminated all the obvious answers? Looked in a mirror, and there is no smear of peanut butter on your nose or upper lip, a leftover of some semi-comatose, hunger-motivated nocturnal ramble?

And I'm unclear, here. Does sweet peanut butter smell any different than ordinary, unsweetened peanut butter?

My compost bin smells like citrus..I have all sorts of rotting stuff in there..including egg shells, twigs, leaves, shredded up brown paper bags, dead flower bouquets, etc. It could be a rotting grapefruit giving the aroma..Anything that isn't meat and can be composted is thrown in it..My trash can gets a big relief..