I'm using 177 now.

I mispoke about the command my client was sending. It was sending the SITE command:
SITE chmod 755 testfile

There are two problems with this
1) Apparently "chmod" is only accepted in all-caps.
2) CHMOD 755 doesn't work...it must be 0755

I know this because I can send custom commands to the server via my client, and using SITE CHMOD 0755 testfile works fine...it's just not the way my client sends it. Can this be changed on the server, so that CHMOD can be lower case and the three digit numeric value works?