function submitForm(form){

	properClickThrough=true;
	// Disabling submit buttons  must come after form.submit(). 
	// Don't know why! Form won't submit otherwise.
	
	var fName = form.name;
    document.forms[fName].submit();
   
	if (document.getElementById("submitCCForm")) {
		document.getElementById("submitCCForm").disabled = true;
	}
	var submitSubForContForm = document.getElementById("submitSubForContForm");
	if (submitSubForContForm) {
		submitSubForContForm.disabled = true;
	}
}

function addInputSubmitEvent(form, input) {
    input.onkeydown = function(e) {
        e = e || window.event;
        if (e.keyCode == 13) { 
        	submitForm(form);
        }
    };
}

function trapEnterKey() {
    var forms = new Array();
    var numForms=0;
    
    if(document.getElementById('freeOptionForm')){
	    forms[numForms] = document.getElementById('freeOptionForm');
	    numForms++;
    }
    if(document.getElementById('subscriptionCreditCardForm')){
	    forms[numForms] = document.getElementById('subscriptionCreditCardForm');
    }
    if(document.getElementById('updateCreditCardForm')){
	    forms[numForms] = document.getElementById('updateCreditCardForm');
    }
	
	    for (var i=0;i < forms.length;i++) {
	        var inputs = forms[i].getElementsByTagName('input');
	
	        for (var j=0;j < inputs.length;j++){
	            addInputSubmitEvent(forms[i], inputs[j]);
	        }
	    }
}

addEvent(window, 'load', trapEnterKey);