sort works wrong after 117452 entries

[Kreuzer IT Support]

Hello there, 
 
I have a backup script running which uses sort in order to process those
files first which are modified last. 
 
I use find (pruning several paths) as input for afio, here for the filelist:

 
 find / -path /proc -prune -o -path /tmp -prune -o -path /opt -prune -o
-path /usr/src -prune -o -path /dev/pts -prune -o -path /dev/shm -prune -o
-path /daten/tmp -prune -o -path /daten/backup -prune -o -path
/daten/install -prune -o -path /daten/src -prune -o -printf '%p; 
address@hidden' |
sort +1 -n -r > /daten/tmp/filelist.txt

You can see the result in http://www.kreuzer-it.com/filelist.txt 
 
As you will notice, the sort for column +1 does it's job only until line
117452. Afterwards, the files are assorted. 
 
My kernel: 
# uname -r
2.4.20-4GB

Hope you can help me, as I don't see how I could update sort. 
 
Best regards, 
Niko Kreuzer