Joomla php error: Warning: Parameter 3 to plgContentPagenavigation::onContentBeforeDisplay() expected to be a reference
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I'm no php coder but I've done a little research and this looks to be an issue with different versions of php - but i could be wrong.

I'm using joomla 2.5 and get this error on checkout (using k2store):

    Warning: Parameter 3 to plgContentPagenavigation::onContentBeforeDisplay() expected to be a reference, value given in */libraries/joomla/event/event.php on line 71
    
    Warning: Parameter 3 to plgContentVote::onContentBeforeDisplay() expected to be a reference, value given in */libraries/joomla/event/event.php on line 71
    
    Warning: Parameter 3 to plgContentPagenavigation::onContentBeforeDisplay() expected to be a reference, value given in */libraries/joomla/event/event.php on line 71
    
    Warning: Parameter 3 to plgContentVote::onContentBeforeDisplay() expected to be a reference, value given in */libraries/joomla/event/event.php on line 71

Line 71 says:

    return call_user_func_array(array($this, $event), $args);

It gives no error on my local host using php5.3.6 but on the development server I get an error with php5.3.10

[There was a similar case here][1] but I did not understand the solution


  [1]: http://stackoverflow.com/questions/8512535/php-error-warning-parameter-1-expected-to-be-a-reference

Maybe this is simple for someone to solve?