code: public CharsetBuilder convert(String nioCharsetName, String cloudhopperCharset) {
  		mappings.add(new CharsetMapping(nioCharsetName, cloudhopperCharset));
  		return this;
  	}
docs: Registers a charset conversion. Conversion is required by Cloudhopper in
  order to use a charset supported by the SMPP protocol.
  
  You can register several charset conversions.
  
  @param nioCharsetName
  the charset used by the Java application
  @param cloudhopperCharset
  the charset supported by the SMPP protocol
  @return this instance for fluent chaining