jquery validation on ascx page

I have not screwed up anything. the validation rule works as expected for a ascx page. here is a steps you can reproduce the behaviour
create aspx page, add a ascx to it e.g.

<uc5:usrapplicant id="usrApplicant1"  runat="server" xmlns:uc5="#unknown"></uc5:usrapplicant> and add another one
<uc5:usrapplicant id="usrApplicant2"  runat="server" xmlns:uc5="#unknown"></uc5:usrapplicant>

in this usercontrol create a control

<input name="txtAddress1" type="text" id="txtAddress1" class="txtAddress1" size="40"  runat="server" />

and in jquery validation add a rule to make the field required.
when rendering in aspx there will be duplicate IDs i.e. txtAddress1, my question is how can I render class as txtAddress2 or something so that I could do my validations. based on those class. thank you