I had a little problem with ocilogon but only with RedHat 8.0. It always returned some kind of error during connection like 'OCISessionBegin - ... invalid character', or 'OCISessionBegin - ... missing or invalid option in ...'
I have finally found what is this problem! You have to change your LANG enviroment variable disabling UTF-8. Example: LANG=en_US.UTF-8 should become LANG=en_US.