### current fpm
$ fpm --cpan-package-reject-from-depends Digest::base --debug-workspace -s cpan -t deb Digest::MD5
Blanking 'provides' field 'perl(Digest::MD5) = 2.59' because it's invalid {:level=>:warn}
Debian tools (dpkg/apt) don't do well with packages that use capital letters in the name. In some cases it will automatically downcase them, in others it will not. It is confusing. Best to not use any capital letters at all. I have downcased the package name for you just to be safe. {:oldname=>"perl-Digest-MD5", :fixedname=>"perl-digest-md5", :level=>:warn}
Downcasing dependency 'libDigest-base-perl' because deb packages  don't work so good with uppercase names {:level=>:warn}
Downcasing dependency 'libXSLoader-perl' because deb packages  don't work so good with uppercase names {:level=>:warn}
Created package {:path=>"libdigest-md5-perl_2.59_amd64.deb"}
plugin directory {:plugin=>"cpan", :pathtype=>:staging_path, :path=>"/tmp/package-cpan-staging-09a6e30a79a7dfd67e5d58a0aa4c16f5ffaa5147d5c40063d987a869f0f0"}
plugin directory {:plugin=>"cpan", :pathtype=>:build_path, :path=>"/tmp/package-cpan-build-89b3145f4a63de73d44b79ec28ee3a63db52974dba68dd5f0eb9c688e4b0"}
plugin directory {:plugin=>"deb", :pathtype=>:staging_path, :path=>"/tmp/package-cpan-staging-09a6e30a79a7dfd67e5d58a0aa4c16f5ffaa5147d5c40063d987a869f0f0"}
plugin directory {:plugin=>"deb", :pathtype=>:build_path, :path=>"/tmp/package-deb-build-c8a6a0a9ed9e17eb8fe43012011a6715c23e5ba3f6287800342f9c6cd5fa"}
$ cd /tmp/package-deb-build-c8a6a0a9ed9e17eb8fe43012011a6715c23e5ba3f6287800342f9c6cd5fa
$ tar -xf control.tar.gz
$ grep ^Depends control
Depends: libdigest-base-perl (>= 1.00), libxsloader-perl, perl (>= 5.006)

### fpm from this PR
$ fpm --cpan-disable-dependency Digest::base --debug-workspace -s cpan -t deb Digest::MD5
Blanking 'provides' field 'perl(Digest::MD5) = 2.59' because it's invalid {:level=>:warn}
Debian tools (dpkg/apt) don't do well with packages that use capital letters in the name. In some cases it will automatically downcase them, in others it will not. It is confusing. Best to not use any capital letters at all. I have downcased the package name for you just to be safe. {:oldname=>"perl-Digest-MD5", :fixedname=>"perl-digest-md5", :level=>:warn}
Downcasing dependency 'libXSLoader-perl' because deb packages  don't work so good with uppercase names {:level=>:warn}
Created package {:path=>"libdigest-md5-perl_2.59_amd64.deb"}
plugin directory {:plugin=>"cpan", :pathtype=>:staging_path, :path=>"/tmp/package-cpan-staging-99aad5497243c8258ad3df05bb8b41baa07ab3672d899b0b97f5f3a96bed"}
plugin directory {:plugin=>"cpan", :pathtype=>:build_path, :path=>"/tmp/package-cpan-build-1ced1496cb4690069dc37ecd105e3ec3e77e87f5a42d32c8a3db00c659cc"}
plugin directory {:plugin=>"deb", :pathtype=>:staging_path, :path=>"/tmp/package-cpan-staging-99aad5497243c8258ad3df05bb8b41baa07ab3672d899b0b97f5f3a96bed"}
plugin directory {:plugin=>"deb", :pathtype=>:build_path, :path=>"/tmp/package-deb-build-084fa0ff5c260557a6d91154c4fd667e886782d9716ec4cf77d29621ae0b"}
$ cd /tmp/package-deb-build-084fa0ff5c260557a6d91154c4fd667e886782d9716ec4cf77d29621ae0b
$ tar -xf control.tar.gz
$ grep ^Depends control
Depends: libxsloader-perl, perl (>= 5.006)