Plugin error when activate

Hi!

My webhost have PHP 5.4 version, but when I activate the plugin inmediately show display this erro message (have activate error messages on wp-config):

Strict Standards: call_user_func_array() expects parameter 1 to be a valid callback, non-static method ChimpMate_WPMC_Assistant::wpmchimp_update_db_check() should not be called statically in /home/agroinsu/public_html/wp-includes/plugin.php on line 496

And not show your fantastic plugin.
Please can you help me? Regards.

https://www.ads-software.com/plugins/chimpmate/