lm3s5d51 booting

Hi,
We are new to stellaris LM3S5D51 microcontroller.
In our project there will be two application codes in different 
locations of flash memory. Depending upon the external condition (may be 
a switch or CRC error during booting ) the boot loader should run any 
one of the application. Is there an option for this in Stellaris boot 
loader?

Regards,
Vetri.