• (kg) added filters to XML DOMConfig and DTD
  
• (ms) Fixed caller level to cspecs by adding one
  
• (ms) Added init_once() and documentation
  
• (ms) Worked around the perl bug that triggers DIE handlers
  even if die() occurs within an eval(). So if you did
  BEGIN { $SIG{DIE} = sub { print "ouch!"; die }; }
  use Log::Log4perl;
  and Time::HiRes wasn't available, the
  eval { require Time::HiRes }
  in PatternLayout.pm triggered the DIE handler. Now there's
  a function module_available() in L4p::Util to check if a
  module is installed.
  
• (ms) Fixed %M cspec in PatternLayout in case a logging
  method is called within one (or more) eval {} block(s).
  caller(n+m) will be called repeatedly if necessary
  to get the next real subroutine. Anonymous subroutines will
  still be called ANON, but this can be overridden by
  defining
  local *ANON = "subroutine_name";
  in them explicitely (thanks, Perlmonks :).