I've recently heard type1 font supports multiple encodings, but defoma
dealt with only single encoding for type1 font.
From defoma 0.5.0, it supports multiple encodings. This document describes
how to add information of multiple encodings to a hintfile.

Please look at the following example.

category type1
begin n021003l.pfa
  FontName = NimbusRomNo9L-Regu
  Charset = ISO8859-1
  Family = Nimbus
  GeneralFamily = Roman
  Weight = Medium
  Width = Variable
  Shape = Upright
  Priority = 20
  X-FontName = -urw-numbus-medium-r-normal--0-0-0-0-p-0-iso8859-1
end

This type1 font, n021003l.pfa, actually contains ISO8859-2, ISO8859-15,
CP1251 and KOI8-R. You have to add hints for each of these encodings
manually using subhints mechanism like:

category type1
begin n021003l.pfa
  FaceNum = 5
  Inherit = Family GeneralFamily Weight Width Shape Priority
  FontName = NimbusRomNo9L-Regu
  Charset = ISO8859-1
  Family = Nimbus
  GeneralFamily = Roman
  Weight = Medium
  Width = Variable
  Shape = Upright
  Priority = 20
  X-FontName = -urw-numbus-medium-r-normal--0-0-0-0-p-0-iso8859-1
  
  Charset1 = ISO8859-2
  X-FontName1 = -urw-numbus-medium-r-normal--0-0-0-0-p-0-iso8859-2
  
  Charset2 = ISO8859-15
  X-FontName2 = -urw-numbus-medium-r-normal--0-0-0-0-p-0-iso8859-15
  
  Charset3 = CP1251
  X-FontName3 = -urw-numbus-medium-r-normal--0-0-0-0-p-0-microsoft-cp1251
  
  Charset4 = KOI8-R
  X-FontName4 = -urw-numbus-medium-r-normal--0-0-0-0-p-0-koi8-r
end

You must write default encoding (ISO8859-1) and common hints (Family,
GeneralFamily, Weight, Width, Shape, Priority) in non-numbered hints,
and write non-default encodings (ISO8859-2, ISO8859-15, CP1251, KOI8-R)
in each numbered hints.
Default/non-default is decided by whether the encoding needs re-encoding
or not.