How we can add static route onto solaris system using command line:
# route add -net 10.0.0.0 10.1.50.250
Add to startup script:
# vi /etc/init.d/static_routes
/usr/sbin/route add -net 10.0.0.0 10.1.50.250
# ln -s /etc/init.d/static_routes S99static_routes