@class missing from choicetable XHTML output

[AirQuick]

Case 1

<choicetable>
    <chrow>
        <choption>opt</choption>
        <chdesc>desc</chdesc>
    </chrow>
</choicetable>

XHTML output:

<thead>
    <tr>
        <th align="left" id="d27e17-option" valign="bottom">Option</th>
        <th align="left" id="d27e17-desc" valign="bottom">Description</th>
    </tr>
</thead>

Problem:

• <tr> and <th> do not have @Class.

Case 2

<choicetable>
    <chhead>
        <choptionhd>opthd</choptionhd>
        <chdeschd>deschd</chdeschd>
    </chhead>
    <chrow>
        <choption>opt</choption>
        <chdesc>desc</chdesc>
    </chrow>
</choicetable>

XHTML output:

<thead>
    <tr class="sthead chhead">
        <th align="left" id="d27e17-option" valign="bottom">opthd</th>
        <th align="left" id="d27e17-desc" valign="bottom">deschd</th>
    </tr>
</thead>

Problem:

• <th> does not have @Class.

Expected

In both cases I would expect these @Class'es:

<thead>
    <tr class="sthead chhead">
        <th align="left" class="stentry choptionhd" id="d27e17-option" valign="bottom">Option</th>
        <th align="left" class="stentry chdeschd" id="d27e17-desc" valign="bottom">Description</th>
    </tr>
</thead>

DITA-OT

2.1 M1