How to force Postgres to use index on ILIKE

I have UTF-8 Postgres 8.1 database on W2K3

Query

SELECT toode, nimetus
FROM toode
WHERE toode      ILIKE  'x10%' ESCAPE '!'
ORDER BY UPPER(toode     ),nimetus  LIMIT 100

runs 1 minute in first time for small table size.

Toode field type is CHAR(20)

How to create index on toode field so that query can use  it ?