opening gamming port for a cisco wrt120n

[mmman]

does any body know how to open these ports . I know you have to do it manually

 

[wirelessnut]

Try here:
http://kb.linksys.com/Linksys/ukp.aspx?pid=96&g=96&vw=1&articleid=17241 (forwarding a range of ports)
http://kb.linksys.com/Linksys/ukp.aspx?pid=96&vw=1&articleid=21470 (forwarding single ports)