An error in the CRC is also a total loss.
If you have n bits of data and a c-bit CRC, you can just as well view
this as n+c bits of data whose CRC is known to be 0. So your techniques
should work just as well for errors in the CRC, as long is you're not
right at a boundary where things work for n bits but not for n+c bits.
Tim Mann tim.mann(a)compaq.com
http://www.tim-mann.org
Compaq Computer Corporation, Systems Research Center, Palo Alto, CA