mechgt - 2011-06-26

The default config.xml file has the following section available indicating that this will enable subtitles:

    <!--
       Uncomment the lines below to get rid of jerky avi playback on the
       DSM320 or to enable subtitles support on the DSM units
    -->
    <custom-http-headers>
      <add header="X-User-Agent: redsonic"/>
    </custom-http-headers>
    <manufacturerURL>redsonic.com</manufacturerURL>
    <modelNumber>105</modelNumber>[/code
I have a DSM-520 running current firmware version 1.06 and can confirm that the following line must be changed to the following in order for subtitles to work.  It must have the "http://www." prefix in order for subtitles to work.  This should likely be changed in the default config.xml file.
[code]    <manufacturerURL>[b]http://www.[/b]redsonic.com</manufacturerURL>[/code]