Paste this in your router:
cat<<'EOF' > /etc/init.d/fix_w1208
#!/bin/sh /etc/rc.common
boot() {
echo 0x2fd4 0x76b5 > /sys/bus/usb-serial/drivers/option1/new_id
}
EOF
chmod +x /etc/init.d/fix_w1208
/etc/init.d/fix_w1208 enable
Then see if its enabled with:
/etc/init.d/fix_w1208 enabled && echo on
It should output βonβ. If yes, then your command will run when the router starts