Javascript that was working in Cognos 10 is not working in Cognos 11 for date calender prompt to show dynamic default date.

Any suggestions please

Cognos 10 working javascript

<script language = "javascript">
var formWR = getFormWarpRequest();
var dateTxtPrompt = formWR.txtDateCountStartDatePrompt
var vCurrDate = new Date();
var vFirstDay= new Date(vCurrDate.getFullYear(), vCurrDate.getMonth(),1);
var vStrDay = [vFirstDay.getUTCFullYear(), vFirstDay.getMonth()+1, vFirstDay.getDate()].join("-");
dateTxtPrompt.value = vStrDay;
</script>