Switch from PHP 5.2 to 5.4 causing error

Hello,

My host will be forcing an upgrade on all users from PHP 5.2 to PHP 5.4. I’m testing it out ahead of time and ran into some trouble. First, all core WP files and plugins are up to date. I also contacted my host support. They did amend something in the PHP.ini file that was off, but it turns out that was unrelated to the issue, and they couldn’t help further.

What is happening is, everything on the site/theme looks fine, accept every page returns a ‘page not found’ error. Here below is a copy of the error log …

[12-Jan-2014 16:29:09 UTC] PHP Warning:  Parameter 1 to ec3_filter_posts_where() expected to be a reference, value given in /public_html/wp-includes/plugin.php on line 256
[12-Jan-2014 16:29:09 UTC] PHP Warning:  Parameter 1 to ec3_filter_posts_join() expected to be a reference, value given in /public_html/wp-includes/plugin.php on line 256
[12-Jan-2014 16:29:09 UTC] PHP Warning:  Parameter 1 to ec3_filter_posts_groupby() expected to be a reference, value given in /public_html/wp-includes/plugin.php on line 256
[12-Jan-2014 16:29:09 UTC] PHP Warning:  Parameter 1 to ec3_filter_posts_fields() expected to be a reference, value given in /public_html/wp-includes/plugin.php on line 256
[12-Jan-2014 16:29:09 UTC] WordPress database error You have an error in your SQL syntax; check the manual that corresponds to your MySQL server version for the right syntax to use near 'FROM wp_posts  WHERE 1=1   ORDER BY wp_posts.post_date DESC' at line 1 for query SELECT    FROM wp_posts  WHERE 1=1   ORDER BY wp_posts.post_date DESC  made by require('wp-blog-header.php'), wp, WP->main, WP->query_posts, WP_Query->query, WP_Query->get_posts

any advice appreciated!