>I have a question about case sensitivity.
>When I SET COLLATE TO "MACHINE" I get .F. for "London"="LONDON".
>But, when I SET COLLATE TO "CZECH" I get .T. for "London"="LONDON".
>
>What is the problem here, and how to control case sensitivity?

First of all, read Help, this is well documented, but spread over several topics. For case independent comparison, use ==.