Ok well thats interesting, in punishers other thread about bragging rights, throwbackchampion posts a photo of 2 1st gen rubies he has with the serial numbers side by side. One burnt on, the other etched/lasered like mine. Thank goodness would appear there are a few like that. I wonder if it has something to do with one of the serial number machines going down or something. It seems really sparatic when they used this type of numbering.
Since you have mentioned this issue I have seen a couple of pairs of x metal frames with the J serial on ebay which appear to be faded, and also seem to be written in a 'finer' font if that makes sense.