Why is this automatic select first option jquery script not working in Internet Explorer?

I have a list where I have implemented the cascading dropdown feature from http://spservices.codeplex.com/. It is working fine, however I want to automatically select the first option in the last dropdown box. The code below works fine in Firefox and Chrome but not in Internet Explorer (IE6/7/8/9). Does anyone know why?

<script language="javascript" type="text/javascript" src="../../../../Hidden/jquery-1.5.2.min.js"></script>
<script language="javascript" type="text/javascript" src="../../../../Hidden/jquery.SPServices-0.6.1.min.js"></script>
<script language="javascript" type="text/javascript">

$(document).ready(function() {

    $().SPServices.SPCascadeDropdowns({
        relationshipList: "Departments",
        relationshipListParentColumn: "Unit",
        relationshipListChildColumn: "CodeDesc",
        parentColumn: "Unit",
        childColumn: "Department"
    });

    $().SPServices.SPCascadeDropdowns({
        relationshipList: "Departments",
        relationshipListParentColumn: "CodeDesc",
        relationshipListChildColumn: "Title",
        parentColumn: "Department",
        childColumn: "DeptCode",
        completefunc: function () { $("select[title=DeptCode]").children().eq(1).attr("selected", "selected"); }
    });  



}); 

Markup:

<tr><td width="190px" valign="top" class="ms-formlabel"><H3 class="ms-standardheader"><nobr>Department<span class="ms-formvalidation"> *</span></nobr></H3></td>开发者_如何学Go;<td width="400px" valign="top" class="ms-formbody"><span dir="none"><span style="vertical-align:middle"><input name="ctl00$PlaceHolderMain$g_6f0051d2_c213_41cd_aa16_6fadb40281aa$ff5_1$ctl00$ctl01" type="text" id="ctl00_PlaceHolderMain_g_6f0051d2_c213_41cd_aa16_6fadb40281aa_ff5_1_ctl00_ctl01" class="ms-lookuptypeintextbox" onfocusout="HandleLoseFocus()" opt="_Select" title="Department" optHid="SPDepartment_Hiddenctl00$PlaceHolderMain$g_6f0051d2_c213_41cd_aa16_6fadb40281aa$ff5_1$ctl00" onkeypress="HandleChar()" onkeydown="HandleKey()" match="" choices="2231011D|1|2231022D|2|2231033D|3|2231033I|4|2232011D|5|2232011I|6|2232022D|7|2232044D|8|2232044I|9|2233011I|10|2233022I|11|2233044I|12|2234011D|13|2234011I|14|2234022D|15|2234022I|16|2234033D|17|2235011D|18|2235011I|19|2236011D|20|2236011I|21|2236022D|22|2236022I|23|2236033I|24|2242401I|25|2242502I|26|2244001I|27|2245001D|28|2245001I|29|2245500I|30|2246027D|31|2246027I|32|2246029D|33|2246029I|34|2246120D|35|2246125D|36|2246125I|37|2246130D|38|2246130I|39|2246254D|40|2246254I|41|2246255I|42|2246346D|43|2246346I|44|2246362D|45|2246362I|46|2246436D|47|2246436I|48|2246440D|49|2246440I|50|2246441D|51|2246801I|52|2249201I|53|2249902D|54" onchange="HandleChange()" /><img alt="Display lookup values" onclick="ShowDropdown('ctl00_PlaceHolderMain_g_6f0051d2_c213_41cd_aa16_6fadb40281aa_ff5_1_ctl00_ctl01');" src="/_layouts/images/dropdown.gif" style="border-width:0px;vertical-align:middle;" /></span><br/></span></td></tr>
<tr><td width="190px" valign="top" class="ms-formlabel"><H3 class="ms-standardheader"><nobr>DeptCode</nobr></H3></td><td width="400px" valign="top" class="ms-formbody"><span dir="none"><span style="vertical-align:middle"><input name="ctl00$PlaceHolderMain$g_6f0051d2_c213_41cd_aa16_6fadb40281aa$ff6_1$ctl00$ctl01" type="text" id="ctl00_PlaceHolderMain_g_6f0051d2_c213_41cd_aa16_6fadb40281aa_ff6_1_ctl00_ctl01" class="ms-lookuptypeintextbox" onfocusout="HandleLoseFocus()" opt="_Select" title="DeptCode" optHid="SPDeptCode_Hiddenctl00$PlaceHolderMain$g_6f0051d2_c213_41cd_aa16_6fadb40281aa$ff6_1$ctl00" onkeypress="HandleChar()" onkeydown="HandleKey()" match="" choices="(None)|0|2231011D|1|2231022D|2|2231033D|3|2231033I|4|2232011D|5|2232011I|6|2232022D|7|2232044D|8|2232044I|9|2233011I|10|2233022I|11|2233044I|12|2234011D|13|2234011I|14|2234022D|15|2234022I|16|2234033D|17|2235011D|18|2235011I|19|2236011D|20|2236011I|21|2236022D|22|2236022I|23|2236033I|24|2242401I|25|2242502I|26|2244001I|27|2245001D|28|2245001I|29|2245500I|30|2246027D|31|2246027I|32|2246029D|33|2246029I|34|2246120D|35|2246125D|36|2246125I|37|2246130D|38|2246130I|39|2246254D|40|2246254I|41|2246255I|42|2246346D|43|2246346I|44|2246362D|45|2246362I|46|2246436D|47|2246436I|48|2246440D|49|2246440I|50|2246441D|51|2246801I|52|2249201I|53|2249902D|54" onchange="HandleChange()" /><img alt="Display lookup values" onclick="ShowDropdown('ctl00_PlaceHolderMain_g_6f0051d2_c213_41cd_aa16_6fadb40281aa_ff6_1_ctl00_ctl01');" src="/_layouts/images/dropdown.gif" style="border-width:0px;vertical-align:middle;" /></span><br/></span></td></tr>

Thanks, David

How about:

$("select[title=DeptCode] option:first").attr("selected",true);