LC_COLLATE=C not working

I have two Linux servers, one is test and one is production. I run Postgres 7.3.3 on both of them. I added a feature to my product that requires sorting like strcmp. So, I did an initdb as follows:

export LC_COLLATE=C
initdb

It fixed the sorting problem.

I have tried to do the same on my production server, and when I do the initdb, it says that LC_COLLATE is C, but it does not sort the same as the test server. Namely, on the test server 'z' < '~' and on the production server 'z' > '~'.

Both servers have /usr/share/locale/C/cups_C, and they are identical.

Can anyone explain to me how to get Postgres to use LC_COLLATE=C on my production server? I have tried installing Postgres 7.3.3 RPM's for RedHat 7.3 and 8.0 and even tried Postgres 7.3.4 (for 8.0). Everything sorts the same as en_US.iso885915.

Thanks in advance.

Robert