Eric,

You will have to use DHTML in order to make that happen.

Place the below code in the PageLoad routine, inside of the "If Not IsPostBack" statement... Be sure the change

txtWhatever

to your text control name.

VB Example:

If txtWhatever.Attributes.Item("onKeyDown") Is Nothing Then
    txtWhatever.Attributes.Add("onKeyDown", _
    "if(event.keyCode == 13){ try { event.cancel = true; document.Form1.submit();} catch(e) { }}")
Else
    txtWhatever.Attributes.Add("onKeyDown", _
    txtWhatever.Attributes.Item("onKeyDown").ToString & _
    "if(event.keyCode == 13){ try { event.cancel = true; document.Form1.submit();} catch(e) { }}")
End If

Hope that helps : )