Folks, I made an update to the karma plugin for 1.3.1 that fixed a problem where karma bars couldn't be displayed on summary pages.
Unfortunately, the update caused static pages (at least the contact form) to print a "Scalar cannot be used as array on line 1123 of serendipity_event_karma.php". I imagine it could break some templates, but it was certainly ugly.
For the short term, the fix is to move the karma plugin before the contact form plugin on the "Configure Plugins" admin page.
I've also updated the code for 1.3.2 (if any) and 1.4 (when it happens).
The other good news is that this should improve the performance of the karma plugin. Oh, so slightly, but I like elegant code and optimized solutions.
Sorry for the inconvenience.