Ajax AutoCompleteExtender property question

I'm trying to use the autocomplete extender from Ajax Toolkit, this works on the main server we are testing on to get the intellisens pulldown to work upon entering text
, but now I have it on another server that is configured the same exact way, i'm wondering if there are any pertinent properties i should be including

<asp:TextBox ID="txtBx" runat="server"></asp:TextBox>
    <ajax:AutoCompleteExtender 
    runat="server" 
    ID="autoComplete1" 
    TargetControlID="txtBx"
    ServiceMethod="GetResult"
    ServicePath="/ajax/Webservice.asmx"
    MinimumPrefixLength="3" 
    CompletionInterval="1000"
    EnableCaching="true"
    CompletionSetCount="20" 
    DelimiterCharacters=";, :"
    ShowOnlyCurrentWordInCompletionListItem="true">
</ajax:AutoCompleteExtender>

thanks

nork