[exim] expansion operator address: case-sensitive?

Hi,

has this to be considered as feature or bug?

message:
Warning: sender mscheld@??? does'nt match reply Mirco Scheld
<mscheld@???>

configure:
  warn condition      = ${if eq{$acl_m9}{1}{yes}{no}}
       condition      = ${if
eq{$sender_address}{${address:$reply_address}}{no}{yes}}
       set acl_m9     = 2

   .....       

  warn condition      = ${if eq{$acl_m9}{2}{yes}{no}}
       message          = X-Check: sender $sender_address does'nt match
reply $reply_address
       log_message    = sender $sender_address does'nt match reply
$reply_address
       !condition     =
${lookup{${domain:$reply_address}}lsearch{/usr/local/etc/exim/domains_to_check}}
       set acl_m9     = 4

Reinhard