gdb-6.2: Reply contains invalid hex digit 59

Can anyone help me decipher this behavior?

Running gdbserver on a mipsel linux-2.4.18 target:

  -bash-2.05b# gdbserver 0:8888 /usr/local/bin/rabl
  Process /usr/local/bin/rabl created; pid = 537

Running gdb on an intel host:

  (gdb) target remote 192.168.5.160:8888
  Remote debugging using 192.168.5.160:8888
  Couldn't establish connection to remote target
  Reply contains invalid hex digit 59
  (gdb) 

Back on the target:

  readchar: Got EOF
  Remote side has terminated connection.  GDBserver will reopen the connection.

What am I doing wrong here?

Thanks,
Dave