I have the same problem using WP version 3.4.2 and plugin version 2.5.3. The server error is:
PHP Parse error: syntax error, unexpected $end in /srv/www/vhosts/iin/wp-content/plugins/wp-publication-archive/lib/class.wp-publication-archive.php on line 765
It is probably something similar to:
http://wordpress.org/support/topic/wp-publication-archive-activation-error
But the solution with removing ?> tag does not work. I am using Linux with PHP 5.3.5 and Apache 2.2.17.
