I noticed the Pidgin "upgrade" right away too, but hadn't got around to doing anything about it until yesterday. In case you don't know, there has been a lot of controversy about the Pidgin developers changing the functionality of the text entry box so it's no longer manually resizable. This irritated a LOT of people, but they refuse to change it back. I use Pidgin every day, and yes, not being able to resize the box is really annoying. The Pidgin project was forked, and a new project named "funpidgin" was formed to pay more attention to users wants and needs. Actually, they are changing the name to "Carrier". The link is
I forgot to write down my steps for installing this. There are instructions for installation on the funpidgin website. You have to uninstall your previous Pidgin and a few libraries, then download and install the deb file. The text area will still be non-resizeable, but go to Tools - Plugins and check the "Entry area manual sizing" checkbox. Now the text area is resizeable.
There is a bit of weirdness in all of this, the forked Pidgin appears identical to the old one. There is nothing on it that says funpidgin or carrier or whatever, so it may not be immediately obvious that you've actually installed anything new.