Cognitive and cultural embeddedness: combining institutional economics and economic sociology
According to this, pederasty is sexual relations between two males, especially when one of them is a minor. Other definitions, like the one that JSBangs found, differ slightly. But otherwise, I think you answered the question yourself: pedophile refers to the attraction, while pederasty refers to the act itself.
seg (plural segs) 1  A metal stud or plate fixed to the sole or heel of a shoe to prevent excessive wear. Also known as a blakey. ( 2 dialect) A callus, an area of hardened skin.