[exim] protect strings from macro expansion

Hi,

is there something to protect a string (like ADDRESS) from macro
expansion, like \N does for string expansion? Otherwise it is not safe to
have fixed strings with uppercase letters in the config file.
A workaround is using ${uc:somestring}, but that seems not nice.

One should should take care of such things, of course, and above all not
use ambigous macro names. But (not only) for sample configs I think it
would be good to have that.


Regards,
Jakob