[exim] Wishlist - case inspecific matching for base 16 md5 c…

I've been playing with crypteq this weekend

after going crazy for a while, i realized that things weren't
matching because many of the various md5 hashing routines ( perl,
python, mysql, postgres, php, commandline) create a lc version of the
hash

exim's crypteq creates a uc version

i have a workaround now to lc both strings

and i understand that many other hash algorithms are indeed case
sensitive -- but the very popular base 16 md5 is not.

so i'd like to wishlist that if we have a base16 md5 -- and only that
version -- the crypteq is case-insensitive to match the native
encryption done by common data stores