# File lib/action_mailer/vendor/tmail-1.1.0/tmail/net.rb, line 267 def exec( mail, top = true ) mail.mime_version = '1.0' if top mail.set_content_type 'multipart', 'mixed' e = encoding(nil) if e and not /\A(?:7bit|8bit|binary)\z/i === e raise ArgumentError, 'using C.T.Encoding with multipart mail is not permitted' end mail.parts.each do |m| exec m, false if m._builtin_multipart? end end