Thanks for the answers.
My prob is that i don't query the database
directly. I use the CASTOR as a persitence-Framework.
I create QOL-queries that are translated into
SQL-Queries by the framework.
So i can't use ILIKE or UPPER(expr) :(
I also can't force the use of a special index.
Howerver, i have to maintain a second field with upper
letters, that i query instead of the orginal field
Thorsten