just for information, there are some ways to extract the flash from a pic mcu with blown fuses.
"Another example is an old PIC16F84 microcontroller from Microchip . The chip erase
operation removes the security protection but at the same time erases the contents of program
and data memories on the chip. The hardware design of the security protection circuit is made
such that the memory is always erased before the security fuse is reset to the initial state.
However it was found that if during the chip erase operation the power supply voltage is
increased to about 10 V for a few milliseconds it causes the memory erase process to terminate
but the security fuse reset finishes as usual making it possible to read the contents of the
memory. Such a high voltage pulse should be applied carefully as increasing its length could
permanently damage the chip. The later revision of this microcontroller, PIC16F84A , has
protection against under- and over-voltage attacks. Any memory modification operations
performed via the programming interface are immediately terminated if the power supply
voltage goes below 3 V or above 6 V. 62
It is not always necessary for the power glitches to be outside the specified power supply
voltage range. For example, in the same PIC16F84A microcontroller the protection mechanism
can be defeated by applying a mere 50 mV glitch after the chip erase operation has started. That
causes termination of the program memory erase operation but not the fuse erase. "
also look here:http://www.cl.cam.ac.uk/~sps32/mcu_lock.html