This must be the oldest bug in SL I know of, has been documented multible times, and I am surprised and also disappointed that it hasn't been fixed yet. I am sorry for any dublicates, that I'm sure exist. Many people have observed this and filed reports, with apparently no reaction from Linden's side, at least as far as I have been able to read through the many posts. I think this is a very annoying bug and I would set it to high priority, although it is not a "showstopper". But if you care for sophisticated graphics as in "Windlight" et al, a graphics engine that constantly displays transparent alpha textures in the wrong order in relation to the viewer, hence showing the textures that should be behind other textures in front of them instead, is in fact a major bummer. A reaction from Linden, that they are aware of this, preferably with some kind of explanation, why it is impossible to fix this, would be a relief after years of living with this bug. Even better it would be if any new viewer would fix it, goes without saying. I want to ask everybody who reads this, to vote for it, to make it an issue!