I'm not sure if this trick will work on the software you are using for your site, but I had similar issues on a system I used to work on when I was in IT many moons ago.
The work around was to have two variables, one which was used for the sort and the other for the display. So in the case of pattern 8000, it would be held as 08000 for the sort and 8000 for the display. That way 08000 would be sorted before 11000, but 8000 would be displayed on the screen.
It's to do with the alphanumeric values of the individual characters in the string. It always looks at the left most character first, then the next and the next.
I'm not even sure if that makes sense reading it back, I mean it does to me, but not sure if it will to anybody else!

But Inwald is all looking good, with forward/back displaying in the same order as menu
