The 0x05 is an excape sequence. The byte following it is one of the commands the the serial bootloader uses. So the 0x05 is ignored for purposes of the CRC
See here:
http://www.microchip.com/download/ap...c16/00851b.pdf (page 3 in particular)
I've already decoded the data stream... all the information you need is in that document except for 2 changes which i noted here:
http://www.chiefdelphi.com/forums/sh...395#post196395
If you have any questions feel free to ask me...