is encoded in u-LAW format.  Based on suggestion from Anthony Baxter
<anthony_baxter@users.sourceforge.net>.

This closes bug #122273.

SourceForge doesn't choke on this batch :-)

I'm not entirely sure this is 100% correct. The patch changes an
\index{persistency} to \index{presistence}, and I don't know what \index{}
does. But it seems to do so persi--er, consistently, so I hope it isn't a
problem.