Could not link driver rlm_sql_oracle: libclntsh.so.10.1

[Ilya]

hello,

i've got Linux 2.6.9-22 and freeRADIUS server v.2.1.1.

after installing and configured FreeRADIUS i try to to start the
daemon with -X parametr and get the error:

Could not link driver rlm_sql_oracle: libclntsh.so.10.1: cannot open shared object file: No such file or directory
Make sure it (and all its dependent libraries!) are in the search path of your system's ld.
/usr/local/etc/raddb/sql.conf[22]: Instantiation failed for module "sql"
/usr/local/etc/raddb/sites-enabled/default[152]: Failed to find module "sql".
/usr/local/etc/raddb/sites-enabled/default[62]: Errors parsing authorize section

can anyone please help to solve this problem or push me to the right
way?

thanks in advance

ilya