Case sensitive contextual filter for MySQL backend

We have a contextual filter in a "view" that should work as "case sensitive", but it doesn't: it seems related to backend used, being MySQL. Generated query is something like "WHERE (( ( __FIELDNAME__ = 'CaseSensitiveValue') )AND(( ...", where equal (i.e. "=" symbol) operator is not case sensitive.

This is a major issue, as it seems there's no way to choose between case sensitivity and moreover it may have different behaviours on different backends.

First we would like if there's any way to set it somehow. Second a temporary work-around would be good (e.g.: we were thinking of adding MySQL's "BINARY" directive somewhere or changing affected column's field collation...): any advice is welcome.

Thankx in advance.