Bug#457247: inexplicable warning stronger-dependency-implies-weaker

[Peter Eisentraut <peter_e@gmx.net>]

Package: lintian
Version: 1.23.41
Severity: normal

Building the ntp package from unstable (1:4.2.4p4+dfsg-2) generates the
following warning:

W: ntp source: stronger-dependency-implies-weaker depends -> recommends ${perl:Depends}
N:
N:   A stronger dependency field implies one of the dependencies in a
N:   weaker dependency field. In other words, the Depends field of the
N:   package requires that one of the packages listed in Recommends or
N:   Suggests be installed, or a package is listed in Recommends as well as
N:   Recommends. Current versions of dpkg-gencontrol will silently fix this
N:   problem by removing the weaker dependency, but it may indicate a more
N:   subtle bug (misspelling or forgetting to remove the stronger
N:   dependency when it was moved to the weaker field).
N:
N:   Refer to 7.2 for details.
N:

The dependencies are:

Depends: adduser, lsb-base (>= 3.0-3), netbase, ${misc:Depends}, ${shlibs:Depends}
Recommends: ${perl:Depends}
Suggests: ntp-doc

which resolves to:

Depends: adduser, lsb-base (>= 3.0-3), netbase, libc6 (>= 2.7-1), libcap1, libreadline5 (>= 5.2), libssl0.9.8 (>= 0.9.8f-1)
Recommends: perl
Suggests: ntp-doc

None of the packages in the Depends line depend on perl, so I don't know what
this warning is trying to say.

-- System Information:
Debian Release: lenny/sid
  APT prefers testing
  APT policy: (990, 'testing'), (500, 'unstable'), (500, 'stable'), (1, 'experimental')
Architecture: i386 (i686)

Kernel: Linux 2.6.18-5-k7 (SMP w/1 CPU core)
Locale: LANG=de_DE.utf8, LC_CTYPE=de_DE.utf8 (charmap=UTF-8)
Shell: /bin/sh linked to /bin/bash

Versions of packages lintian depends on:
ii  binutils            2.18.1~cvs20071027-1 The GNU assembler, linker and bina
ii  diffstat            1.45-2               produces graph of changes introduc
ii  dpkg-dev            1.14.7               package building tools for Debian
ii  file                4.21-3               Determines file type using "magic"
ii  gettext             0.16.1-2             GNU Internationalization utilities
ii  intltool-debian     0.35.0+20060710.1    Help i18n of RFC822 compliant conf
ii  libparse-debianchan 1.1.1-1              parse Debian changelogs and output
ii  liburi-perl         1.35.dfsg.1-1        Manipulates and accesses URI strin
ii  man-db              2.5.0-4              on-line manual pager
ii  perl [libdigest-md5 5.8.8-12             Larry Wall's Practical Extraction 

lintian recommends no packages.

-- no debconf information