workaround_split.rb

module Phony
  class << self
    alias_method :split_default, :split

    def split(phone_number)
      split_default(phone_number).map {|part|
        puts "#{part.class.inspect} -> #{part.inspect}"
        if !part.is_a?(Fixnum) && !part.is_a?(String) || (part.respond_to?(:match) && part.match(/Phony::/))
          part = nil
        end
        part
      }
    end
  end
end

I wonder if this would cover all the bases as well?

module Phony
  class << self
    alias_method :split_default, :split

    def split(phone_number)
      split_default(phone_number).map { |part| part if part.respond_to? :to_str }
    end

  end
end