I just installed the 1.2.2 release, and everything went reasonably well. I used the update.php script. However, I did notice one thing that appears to be a bug. The $wgAllMessagesEn array includes values for "sitesupport" and "sitesupportpage," and the instructions say that if "sitesupportpage" is not set, the donations link "won't appear." The problem is that it didn't appear even when I DID set "sitesupportpage" to the URL of our donations page.
I was able to get it working by adding the following line to LocalSettings.php:
$wgSiteSupportPage = "https://www.groundspring.org/donate/index.cfm?ID=2344-0%7C1118-0";
I figured this out by noticing that inside DefaultSettings.php, there is a line that reads:
$wgSiteSupportPage = "";
This should do something more intelligent, such as setting $wgSiteSupportPage to the value of "sitesupportpage," shouldn't it?
--Sheldon Rampton