Currently when a plugin hasn't implemented getInfo() and additionally the "new" (and required) plugin.info.txt file is missing the plugin base class triggers a warning (see http://github.com/splitbrain/dokuwiki/blob/master/inc/plugin.php#L36
). This causes also some additional warnings: "Warning: array_merge(): Argument #1 is not an array in .../lib/plugins/plugin/classes/ap_info.class.php on line 32" and "Warning: Invalid argument supplied for foreach() in .../lib/plugins/plugin/classes/ap_info.class.php on line 38" and as warnings are displayed the header information cannot be modified which (may) lead to a wrong character encoding.
This is the scenario when warnings are printed out, they might also vanish in a logfile and never be noticed. I think this should be changed to trigger a DokuWiki error message that points to the documentation explaining how to create that info file and states that the plugin is somehow broken and perhaps even provides some information on how the plugin folder should be named. Additionally the code should be changed so that no further warnings are triggered when that problem occurs.