[exim] case insensitive regex matching?

Hej,

when I'm saying match {<string1>}{<string2>} in a string expansion,
pattern matching is done case sensitive. Is it possible to ignore case
differences? I can't do just a lc{<string1>} in this case, as the
problem are uppercase letters in the regex, not in the matched string.
And lc{<string2>} of course may not do what is expected.


TIA,
daniel