e2mmap.rb - for ruby 1.1
    $Release Version: 2.0$
    $Revision: 1.10 $
    by Keiju ISHITSUKA

Usage:

class Foo
  extend Exception2MessageMapper
  def_e2message ExistingExceptionClass, "message..."
  def_exception :NewExceptionClass, "message..."[, superclass]
  ...
end

module Error
  extend Exception2MessageMapper
  def_e2meggage ExistingExceptionClass, "message..."
  def_exception :NewExceptionClass, "message..."[, superclass]
  ...
end
class Foo
  include Error
  ...
end

foo = Foo.new
foo.Fail ....

module Error
  extend Exception2MessageMapper
  def_e2message ExistingExceptionClass, "message..."
  def_exception :NewExceptionClass, "message..."[, superclass]
  ...
end
class Foo
  extend Exception2MessageMapper
  include Error
  ...
end

Foo.Fail NewExceptionClass, arg...
Foo.Fail ExistingExceptionClass, arg...