When name and e-mail are quoted in ~/.gitconfig, such as:
[user]
name = "Mister Dude"
email = "dude@example.com"

the Rakefile that Jeweler generates for a new project double quotes author and email:
Jeweler::Tasks.new do |gem|
gem.name = "the-perfect-gem"
gem.summary = %Q{TODO}
gem.email = ""dude@example.com""
gem.homepage = "http://github.com/foo/the-perfect-gem"
gem.authors = [""Mister Dude""]
end

This is because ruby-git parses ~/.gitconfig directly instead of using the system commands.