Use of leading dot (period) causing sorting to break

Use of leading dot (period) causing sorting to break

Spend days trying to figure out why my sorting didn't. Two columns
just refused to get sorted. Finally, decided to manually enter the
data into the columns and amazingly, that fixed it. I was able to
single out items what had ".NET" in front of them, which worked after
I removed the dots.
To recreate the problem add an item with a leading dot (period) to any
column beyond the first one.
Example table:
<table cellspacing="1" class="tablesorter" id="grdTest">
<thead>
<tr>
    <th>Name</th>
    <th>Major</th>
    <th>Sex</th>
</tr>
</thead>
<tbody>
<tr>
    <td>Student01</td>
    <td>.NET Languages</td>
    <td>male</td>
</tr>
<tr>
    <td>Student02</td>
    <td>Mathematics</td>
    <td>female</td>
</tr>
<tr>
    <td>Student03</td>
    <td>Languages</td>
    <td>male</td>
</tr>
</table>
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