instant client RH EL 4.4 sqlplus

Hello,
Am trying to configure instant client 10_2 on RH EL 4.4.
So have set LD_LIBRARY_PATH, PATH and ORACLE_HOME to the dir where the
unzipped instant client lives.
However cannot seem to connect to remote DB using sqlplus like so:
sqlplus user/password@[EMAIL PROTECTED]
 6 initializing SQL*Plus
Message file sp1<lang>.msb not found
SP2-0750: You may need to set ORACLE_HOME to your Oracle software
directory

But if I invoke sqlplus user/password@[EMAIL PROTECTED]
 on the remote box this
works purfect.

I guess I am missing something, but not being an expert I am not sure
what!

Anyone care to advise?

TIA

Kevin

..