case insensitive search with greek characters

Hi all,

I 'm testing postgres 8.0 beta 1 an i have the following problem. I have
a field with value Γιάννης. If i execute the following query it does not
returns any rows.

select * from test where descr ilike '%γιαννης%'

if i change the query to

select * from test where descr ilike '%γιάννης%'

everything is fine. As you can see the problem is at char α .
I 'm using ENCODING = 'ISO_8859_7'. I also tried with unicode but no luck.

An suggestions?

Thanks,
Gvre