private Byte decodeByte(byte[] in) {
    assert in.length == 2 : "Wrong length for a byte";
    byte value = in[1];
    return Byte.valueOf(value);

  }
Handles old whalin (tested with v1.6) encoding: data type is in the first
byte of the value.

@author bpartensky
@since Oct 16, 2008
src/main/java/net/spy/memcached/transcoders/WhalinV1Transcoder.java