sort order in Nautilus

["Kotrla Vitezslav" <kotrla ceb cz>]

A friend of mine is bothered by this one. He is versioning
his work like this

  001.txt
  002.txt
  ...

which is apparently no problem. Now he makes revision in 001.txt,
saves as 001a.txt, next revision is 001b.txt etc.. Problem is that
'by name' sort order in Nautilus 2.6.3 makes this list

  001a.txt
  001b.txt
  001.txt

but he would (and me too) expect 001.txt in the first place.

Is it bug, feature, or is there any sorting rationale behind?

Thanks for explanation,

Vit Kotrla