Hi,
Router1#configure terminal
Enter configuration commands, one per line. End with CNTL/Z.
Router1(config)#service config
Router1(config)#boot network tftp Network-auto 172.25.1.1
Router1(config)#boot host tftp Routers-auto 172.25.1.1
Router1(config)#end
Router1#
You need to have Network-auto and Routers-auto files [wheere you would have the configuration]in the TFTP server.
-> Sushil