Oh! I will automate that for the plugin in the next version. For now (if you can’t wait) you can make a quick edit yourself to this file:
mf-gig-calendar/mf-gig-calendar.php
Just add the link to the .js file that contains your language – put it between lines 209-210:
echo '<script type="text/javascript" src="' . $siteurl . '/wp-content/plugins/' . basename(dirname(__FILE__)) . '/datepicker-4.0.2/jquery.datepick.js"></script>';
echo '';
Add a line between the two so it looks like this and loads your PL language:
echo '<script type="text/javascript" src="' . $siteurl . '/wp-content/plugins/' . basename(dirname(__FILE__)) . '/datepicker-4.0.2/jquery.datepick.js"></script>';
echo '<script type="text/javascript" src="' . $siteurl . '/wp-content/plugins/' . basename(dirname(__FILE__)) . '/datepicker-4.0.2/jquery.datepick-pl.js"></script>';
echo '';
Hope that’s clear.
Matthew