[exim] wildlsearch bug?

Hi,

When using ${match} or ${sg} with a regular expression, it is case
sensitive:

root@clayman:~# exim4 -be '${if match{FOO}{\N^[a-z]+$\N}{true}{false}}'
false
root@clayman:~#

However, and here's what I think is a bug. Wildlsearch seems to be case
insensitive when doing regex matches:

root@clayman:~# echo -ne '\N^[a-z]+$\N' > /tmp/test
root@clayman:~# exim4 -be
'${lookup{FOO}wildlsearch{/tmp/test}{true}{false}}'
true
root@clayman:~#

I expected that to return false... Even if I try to force the regex to
be case sensitive it doesn't behave so:

root@clayman:~# echo -ne '\N^(?-i)[a-z]+$\N' > test
root@clayman:~# exim4 -be
'${lookup{FOO}wildlsearch{/tmp/test}{true}{false}}'
true
root@clayman:~#

Shall I plonk this into bugzilla, or have I just missed some
documentation that explains this behaviour? I can't find any...

Mike