can perl do it?

Irrespective of what the definition of "it" is, the answer is "yes."

I've used LWP::Simple for this kind of stuff and it works just swell. Here is some pseudo code --

1 connect to the site
2 authenticate
3 move to the "certain area"
4 determine the freshness of the patches
5 download
[download]

Heck, I just rewrote your original question. ;-)