[CyberAlien]

You can't have more than one background image for css class.

The only solution is to put nested <div> in table cells like this: <td class="alt1"><div class="altdiv">contents of table cell</div></td> and put different background images for it. Because div might not have full height of table cell I suggest to put top image background for altdiv and bottom image background for alt1/alt2/alt3.

In extra css add code like this:

.alt1 .altdiv, .alt1Active .altdiv { 
  background-image: url(whatever.gif);
  background-repeat: repeat-x;
  background-position: top left;
}
.alt2 .altdiv, alt2Active .altdiv {
 ... same as above, but for alt2
}
.alt3 .altdiv {
 ... same as above, but for alt3
}