Hey, i have a jumpmenu

Code:
<form name="jump" target="parent">
  <select name="parent" id="parent" onChange="MM_jumpMenu('parent',this,0)">
<option value="kylp160.html">Kylpytynnyri  160 cm - 849.00 </option>
<option value="kylp180.html" selected>Kylpytynnyri  180 cm - 909.00 </option>
    <option value="kylp200.html">Kylpytynnyri  200 cm - 959.00 </option>
    <option value="kylp220.html">Kylpytynnyri  220 cm - 1029.00 </option>
    <option value="kylp240.html">Kylpytynnyri  240 cm - 1129.00 </option>
  </select>
  </form>
Javascript code ( default jumpmenu one)
Code:
<script type="text/javascript">
function MM_jumpMenu(targ,selObj,restore){ //v3.0
  eval(targ+".location='"+selObj.options[selObj.selectedIndex].value+"'");
  if (restore) selObj.selectedIndex=0;
}
</script>
The code for iframe where the page should change in
Code:
<iframe src="http://martinlougas.eu/hind1.html" style="border:0px #FFFFFF none;" scrolling="no" id="parent" name="parent" frameborder="0" marginheight="0px" marginwidth="0px" height="400px" width="868px"></iframe>
So my problem is, when i change a value from the jumpmenu it jumps to a wrong page. The page itself is http://kylpytynnyrit.eu/hinnat and the iframe is there. once you select something from the jumpmenu, it jumps to a page http://martinlougas.eu/something.html. Is it possible for it NOT to jump on other domain, but change the window inside the iframe ? Hard for me to explain that in english, im sorry.

Thanks in advance