Change all table cells to have a border

Change all table cells to have a border

See the table code below. Because this table is created by a third party application, I can't modify their code. So, I'm stuck trying to find other ways to change the table styles. I figured jQuery would be a great way to accomplish this, but I can't figure out the correct code. Can someone show me how to change all cells, or certain cells (dddefault and ddlabel) to have a border? I've gotten close, but it only affects the first cell.
Thanks in advance!

<TABLE CLASS="datadisplaytable" SUMMARY="This layout table is used to present the weekly course schedule." WIDTH="80%">
<TR>
<TH CLASS="ddheader" scope="col" >&nbsp;</TH>
<TH CLASS="ddheader" scope="col" >&nbsp;&nbsp;&nbsp;Monday&nbsp;&nbsp;&nbsp;</TH>
<TH CLASS="ddheader" scope="col" >&nbsp;&nbsp;&nbsp;Tuesday&nbsp;&nbsp;&nbsp;</TH>
<TH CLASS="ddheader" scope="col" >&nbsp;&nbsp;&nbsp;Wednesday&nbsp;&nbsp;&nbsp;</TH>
<TH CLASS="ddheader" scope="col" >&nbsp;&nbsp;&nbsp;Thursday&nbsp;&nbsp;&nbsp;</TH>
<TH CLASS="ddheader" scope="col" >&nbsp;&nbsp;&nbsp;Friday&nbsp;&nbsp;&nbsp;</TH>
<TH CLASS="ddheader" scope="col" >&nbsp;&nbsp;&nbsp;Saturday&nbsp;&nbsp;&nbsp;</TH>
<TH CLASS="ddheader" scope="col" >&nbsp;&nbsp;&nbsp;Sunday&nbsp;&nbsp;&nbsp;</TH>
</TR>
<TR>
<TH ROWSPAN="4" CLASS="ddlabel" scope="row" >9am</TH>
<TD CLASS="dddefault">&nbsp;</TD>
<TD CLASS="dddefault">&nbsp;</TD>
<TD CLASS="dddefault">&nbsp;</TD>
<TD CLASS="dddefault">&nbsp;</TD>
<TD CLASS="dddefault">&nbsp;</TD>
<TD CLASS="dddefault">&nbsp;</TD>
<TD CLASS="dddefault">&nbsp;</TD>
</TR>
...
<TR>
<TD CLASS="dddefault">&nbsp;</TD>
<TD ROWSPAN="3" CLASS="ddlabel"><A HREF="xxx.xxx?term_in=200920&amp;crn=12345">ACC 201-009<BR>25296 Class<BR>9:30 am-10:15 am<BR>BTC 105</A></TD>
<TD CLASS="dddefault">&nbsp;</TD>
<TD ROWSPAN="3" CLASS="ddlabel"><A HREF="xxx.xxx?term_in=200920&amp;crn=23456">ACC 201-009<BR>25296 Class<BR>9:30 am-10:15 am<BR>BTC 105</A></TD>
<TD CLASS="dddefault">&nbsp;</TD>
<TD CLASS="dddefault">&nbsp;</TD>
<TD CLASS="dddefault">&nbsp;</TD>
</TR>
...
<TR>
<TD CLASS="dddefault">&nbsp;</TD>
<TD CLASS="dddefault">&nbsp;</TD>
<TD CLASS="dddefault">&nbsp;</TD>
<TD CLASS="dddefault">&nbsp;</TD>
<TD CLASS="dddefault">&nbsp;</TD>
<TD CLASS="dddefault">&nbsp;</TD>
<TD CLASS="dddefault">&nbsp;</TD>
</TR>
</TABLE>