Sadly not, it's not possible to do that AFAIK because if it were, it would pose a security risk (if you were able to access a nested site, it'd mean that the "main" site could phish any info you input to the nested site, which would obviously be bad). I looked into this before to try and make a solution for bookmarklets on the PSP, which didn't work due to this limitation/feature.
EDIT: OK, it is possible, but you won't like the solution. What you must do anytime you want to use it is open the FAQ, then type this into the address bar:
javascript:void(s=prompt('Find text:',''));s='('+s+')';x=new RegExp(s,'gi');rn=Math.floor(Math.random()*100);rid='z' + rn;b = document.body.innerHTML;b=b.replace(x,'<span name=' + rid + ' id=' + rid + ' style=\'color:#000;background-color:yellow; font-weight:bold;\'>$1</span>');void(document.body.innerHTML=b);alert('Found ' + document.getElementsByName(rid).length + ' matches.');window.scrollTo(0,document.getElementsByName(rid)[0].offsetTop);
It's a javascript bookmarklet to search within a page. The PSP cannot bookmark javascript URLs, so you would have to type this thing out every single time. It'd cause a little box to appear where you type in a search term, and then it'd highlight it in yellow and jump to the first instance of it. (I think if you chanfe the [0] towards the end to [1] it'll jump to the second, [2] for the third etc.)
Given this, I didn't try it. You feel free to do so. (If you do, then you will be able to access it from the "History" section on one of the keyboards that comes up when you go to the address bar. The keyboard with the http:// button. This way, you can use it again without retyping it, provided it was recently that you used it)