lmao now this is funny! i had this exact same issue and found a solution! the problem is your custom user agent! opera's custom user agent is set so that websites see your phone as a mobile device, now we dont want that do we? thats why when you type in some websites like facebook.com it automatically redirects you to the mobile version of the site. this is also why the reply/pm box is not selectable on some websites. the box appears but you cant enter text!
i made a thread on it a while ago, heres the link
http://forum.ppcgeeks.com/showpost.php?p=1610789
ive also found that leaving the custom user agent blanks works as well. i hope this helps you guys as this truly drove me crazy before i found a resolution. Dont forget to hit thanks and let me know if you guys need more help!