Googling "dallas maxim crc" turned up a few links, one of which http://arduino.cc/forum/index.php?topic=37648.0;wap2 offers:

// Dallas 1-wire 16-bit CRC calculation. Developed from Maxim Applicat
+ion Note 27.
uint16_t crc16( uint8_t *data, uint8_t len)
{
      uint16_t crc=0;
      
      for (uint8_t i=0; i<len;i++) 
      {
            uint8_t inbyte = data[i];
            for (uint8_t j=0;j<8;j++) 
            {
                  uint8_t mix = (byte(crc)^ inbyte) & 0x01;
                  crc = crc >> 1;
                  if (mix) 
                        crc = crc ^ 0xA001;
                  
                  inbyte = inbyte >> 1;
            }
      }
      return crc;
}
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Just translate it to perl, and you're done...

...roboticus

When your only tool is a hammer, all problems look like your thumb.