I managed to get this done by hard-coding, but someone with a plugin or something like that - this would be much appreciated.
The hard-coding was as follows :
In qa-page-question-view.php I used this code :
if ($question['answerbutton']) // don't show if shown by default
$buttons['answer']=array(
'tags' => 'name="q_doanswer" id="q_doanswer" href="#a_form" type="button" onclick="var e=\'anew\' ? document.getElementById(\'anew\') : null;var t=$(e).offset().top;var h=$(e).height()+16;var wt=$(window).scrollTop();var wh=$(window).height();if ( (t<wt) || (t>(wt+wh)) ) qa_scroll_page_to(t);else if ((t+h)>(wt+wh)) qa_scroll_page_to(t+h-wh);if (e.qa_focus)e.qa_focus();"',
//onclick="return qa_toggle_element(\'anew\')"',
'label' => qa_lang_html('question/answer_button'),
'popup' => qa_lang_html('question/answer_q_popup'),
);
instead of :
if ($question['answerbutton']) // don't show if shown by default
$buttons['answer']=array(
'tags' => 'name="q_doanswer" id="q_doanswer" onclick="return qa_toggle_element(\'anew\')"',
'label' => qa_lang_html('question/answer_button'),
'popup' => qa_lang_html('question/answer_q_popup'),
);