PVS-Studio warning V547 for UCSniff

int initialize_g726_decoder(unsigned long *hDecoder)
{
  *hDecoder = EasyG726_init_decoder();
  if(*hDecoder<0)
   return -1;
  return 0;
}

This suspicious code was found in UCSniff project by PVS-Studio static code analyzer.
Warning message is:
V547 Expression '* hDecoder < 0' is always false. Unsigned type value is never < 0.  g726_decoder.c 11

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