1 - message queueing/dequeuing
     2 - remote file/dir open/close
     4 - DESTROY calls
     8 - hexdumps of incomming packets
    16 - hexdumps of outgoing packets
    32 - _do_io, _conn_lost
    64 - _set_error, _set_status
   128 - on the fly transformations
   256 - add timestamp and process id 
   512 -
  1024 - hexdump of sysreads
  2048 - hexdump of syswrites
  4096 - _rel2abs
  8192 - mkpath
 16384 - put method
 32768 - recursive methods
 65536 - password login
131072 - private backend