//requires eventhandling.js

var checkRequiredFieldsSetup = false;
function setupRequiredFields()
{
    var argLength = requiredFields.length;
    for(var i=0; i < argLength; i++)
    {
        $(requiredFields[i]).observe('keyup', checkRequiredFields)
    }
    
}

function checkRequiredFields()
{
    if(!window.checkRequiredFieldsSetup){
        setupRequiredFields();
        checkRequiredFieldsSetup = true;
     }

    var argLength = requiredFields.length;
    
    for(var i=0; i < argLength; i++)
    {
        var field = $(requiredFields[i]); 
        if(field.value == "")
        {
            $(submitbutton).disabled = true;
            return;
        }
    }

    $(submitbutton).disabled = null;
}