/usr/bin/sort behaving differently on two Solaris 10 servers

 We have a fairly complicated delimited file for an important application.  A script using sort was written a few years ago and has been working fine since.  We're upgrading the application on new hardware, and now the script sorts the same file differently.

The script builds a "key" out of several fields in the raw file and sorts.  It's a Perl script but calls /usr/bin/sort.   Unfortunately the modified sort is breaking the underlying application.

/usr/bin/sort -o /tmp/sorted_file -k 1.1,1.78 /tmp/raw_file

I'm not the author, but I've taken the raw file and manually run sort against it with this same result.