G.723.1 vs. G.723

What is the difference between G.723.1 and G.723? And I don't mean the numerical difference, as in 0.1 :-) Are they the same thing, and people are just being imprecise when they refer to G.723.1 as "G.723?" For SuperOp! scheduling, they were both listed as two of the possible audio codecs, as if they were different. Does anyone truly support G.723 but not G.723.1? If so, I've never come across such an implementation. Also, what is the history of G.723.1? I believe the current version is something called 5.1. Is this correct? Were there some intermediate versions?

Paul Long Smith Micro Software, Inc.