ValdikSS

exec [-cl] [-a name] [command [arguments]]
    If command is specified, it replaces the shell.  No new process  is  created.   The
    arguments become the arguments to command.  If the -l option is supplied, the shell
    places a dash at the beginning of the zeroth argument passed to command.   This  is
    what  login(1)  does.   The  -c  option causes command to be executed with an empty
    environment.  If -a is supplied, the shell passes name as the  zeroth  argument  to
    the  executed  command.   If  command  cannot  be  executed for some reason, a non-
    interactive shell exits, unless the execfail shell  option  is  enabled.   In  that
    case,  it returns failure.  An interactive shell returns failure if the file cannot
    be executed.  If command is not specified, any  redirections  take  effect  in  the
    current  shell,  and  the return status is 0.  If there is a redirection error, the
    return status is 1.

https://sources.debian.org/data/main/e/exim4/4.96-15%2Bdeb12u5/debian/patches/78_01-Fix-MIME-parsing-of-filenames-specified-using-multip.patch
https://sources.debian.org/data/main/e/exim4/4.96-15%2Bdeb12u5/debian/patches/78_02-MIME-support-RFC-2331-for-name-.-Bug-3099.patch

export QUILT_PATCHES=debian/patches
export QUILT_REFRESH_ARGS="-p ab --no-timestamps --no-index" 
quilt import 78_01-Fix-MIME-parsing-of-filenames-specified-using-multip.patch
quilt import 78_02-MIME-support-RFC-2331-for-name-.-Bug-3099.patch
quilt push -a

Кто может понимает что происходит?

dh_installdeb(1) automatically flags any files under the /etc directory as conffiles, so if your program only has conffiles there you do not need to specify them in this file. For most package types, the only place conffiles should ever be is under /etc, and so this file doesn't need to exist.