T3 could not support on this case, but I suggest you doing the following way:
1) Make templates/your_template/blocks/more.php file
<?php if ($this->countModules('header') || $this->countModules('header-text')): ?>
<div id="ja-both-module">
<?php if ($this->countModules('hotline')): ?>
<div id="ja-header">
<jdoc:include type="modules" name="header" style="raw" />
</div>
<?php endif; ?>
<?php if ($this->countModules('vm-cart')): ?>
<div id="ja-header-text">
<jdoc:include type="modules" name="header-text" style="raw" />
</div>
<?php endif; ?>
</div>
<?php endif; ?>
2) Go to admin->Extensions->Template Manager->Edit your template->Layouts Tabs->Edit Default
<block name="more" type="more"></block>