[RESOLVED] Javascript Pop up

Hi guys

I put together a little pop up calendar and it worked fine while I was testing it in a couple of stand alone aspx pages.

One page fires the pop up (an aspx page with a calendar).
select a date and it fills in a textbox on the opener.

The trouble seems to be I'm using a master page in my app so:

Code:

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js.Append("window.opener.document.frmCalls.txtDate.value='" & str & "';")

---

Doesn't work because 'frmCalls' doesn't exist. How do I refer to txtDate?

I tried using var senderTxtBox = window.opener.document.getElementById("txtDate"), but Strike 2

Any ideas?