can not enable this modul

when I try to install this modul I get this error:

Warning: Call-time pass-by-reference has been deprecated; If you would like to pass it by reference, modify the declaration of array_merge(). If you would like to enable call-time pass-by-reference, you can set allow_call_time_pass_reference to true in your INI file. in /is/htdocs/wp1059982_DVYR4P82F4/www/vertikaldenker/sites/all/modules/wizard/Wizard_Form.class.php on line 114

Warning: Call-time pass-by-reference has been deprecated; If you would like to pass it by reference, modify the declaration of array_merge(). If you would like to enable call-time pass-by-reference, you can set allow_call_time_pass_reference to true in your INI file. in /is/htdocs/wp1059982_DVYR4P82F4/www/vertikaldenker/sites/all/modules/wizard/Wizard_Form.class.php on line 117