The tabs went missing after upgrading from 1.7. to 1.8.3. Hopefully the attached picture shows the problem, namelly that the tabs are gone and instead showing as a bulleted list in the beginning of page. I tried to use a couple of other themes like standard theme, but that didn't fix it. What could be wrong? This is the html-code from that part:
<div id="content">
<table id="layout-table"><tr><td id="middle-column">
<div class="tabtree">
<ul class="tabrow0">
<li class="first onerow here selected"><a href="#" title="Tietoa"><span>Tietoa</span></a><div class="tabrow1 empty"> </div>
</li>
<li><a href="http://verkkokoulu.lieto.fi/mod/quiz/report.php?q=110" title="Tulokset"><span>Tulokset</span></a> </li>
<li><a href="http://verkkokoulu.lieto.fi/mod/quiz/attempt.php?q=110" title="Esikatselu"><span>Esikatselu</span></a> </li>
<li class="last"><a href="http://verkkokoulu.lieto.fi/mod/quiz/edit.php?quizid=110" title="Muokkaa "><span>Muokkaa </span></a> </li>
</ul>
</div><div class="clearer"> </div>