Remove Conflict og two diffrent Jqueryies on one page:)

Hello every one cam any one help me.
i m using two diffrent jqueries on 1 page.
1 query for tabs
2nd for drop down chek box list.
when i open 1 tab.if i click on that tab content area.it starts loading other jquery.

can anyone tell me how to remove conflict.

/////////////////////////////////////////////////////////////////////////////////////////////////
<script type="text/javascript" src="jquery-1.2.3.pack.js"> </script>
<script type="text/javascript">

function loadTabContent(tabUrl){
$("#preloader").show();
jQuery.ajax({
url: tabUrl,
cache: false,
success: function(message) {
jQuery("#tabcontent").empty().append(message);
$("#preloader").hide();
}
});
}

jQuery(document).ready(function(){

$("#preloader").hide();
jQuery("[id^=tab]").click(function(){

// get tab id and tab url
tabId = $(this).attr("id");
tabUrl = jQuery("#"+tabId).attr("href");

jQuery("[id^=tab]").removeClass("current");
jQuery("#"+tabId).addClass("current");

// load tab content
loadTabContent(tabUrl);
return false;

});
});

</script>

<script type="text/javascript">
function validate_required(field,alerttxt)
{
with (field)
{
if (value==null||value=="")
{alert(alerttxt);return false;}
else {return true}
}
}function validate_form(thisform)
{
with (thisform)
{
if (validate_required(name,"Please Enter a Name!")==false)
{email.focus();return false;}
}
}
</script>
////////////////////////////////////////////////////////////////////////////////////////////////////////////////

////////////////////////////////////////////////////////////////////////////////////////////////////////////
2nd Jquery

<script type="text/javascript" src="src/jquery-1.4.4.min.js"></script>


<script type="text/javascript" src="jquery-ui-1.8.4.custom.min.js"></script>


<!-- Include the DropDownCheckList supoprt -->
<script type="text/javascript" src="src/ui.dropdownchecklist.js"></script>

<!-- Apply dropdown check list to the selected items -->
<script type="text/javascript">

$(document).ready(function() {
$(".s1").dropdownchecklist();
$(".s3").dropdownchecklist( { icon: {}, width: 150 } );
$(".s3a").dropdownchecklist( { width: 150 } );
$(".s4").dropdownchecklist( { icon: {}, maxDropHeight: 150, width: 150 } );
$(".s4a").dropdownchecklist( { icon: { placement: 'right', toOpen: 'ui-icon-arrowthick-1-s'
, toClose: 'ui-icon-arrowthick-1-n' }
, maxDropHeight: 150, width: 150 } );
$(".s5").dropdownchecklist( { firstItemChecksAll: true } );
$(".s6").dropdownchecklist();
$("#s7").dropdownchecklist();
$("#s7a").dropdownchecklist( { closeRadioOnClick: true } );
$(".s8").dropdownchecklist( { emptyText: "Please Select...", width: 150 } );
$(".s9").dropdownchecklist( { textFormatFunction: function(options) {
var selectedOptions = options.filter(":selected");
var countOfSelected = selectedOptions.size();
switch(countOfSelected) {
case 0: return "Nobody";
case 1: return selectedOptions.text();
case options.size(): return "Everybody";
default: return countOfSelected + " People";
}
} });
$(".s10").dropdownchecklist( { forceMultiple: true, onComplete: function(selector) {
var values = "";
for( i=0; i < selector.options.length; i++ ) {
if (selector.options.selected && (selector.options.value != "")) {
if ( values != "" ) values += ";";
values += selector.options.value;
}
}
alert( values );
} });
$(".s11").dropdownchecklist( { firstItemChecksAll: true } );
$(".s12").dropdownchecklist( { width: 250 } );
$(".s13").dropdownchecklist( { width: 150, onComplete: function(selector) {
var values = "";
for( i=0; i < selector.options.length; i++ ) {
if (selector.options.selected && (selector.options.value != "")) {
if ( values != "" ) values += ";";
values += selector.options.value;
}
}
alert( values );
} });
$(".s14").dropdownchecklist( { width: 150 } );

});
</script>
///////////////////////////////////////////////////////////////////////////////////////////////////////////////////

 

remove <script type="text/javascript" src="jquery-1.2.3.pack.js"> </script> then check .