function checkForm(f)
{   
	// set error value to empty
	var error = '';
	error +=f.first_name.value=='' ? '\n- first name':'';   
	error +=f.last_name.value=='' ? '\n- last name':'';   	
	error += f.email.value.indexOf("@") == -1 || f.email.value.indexOf(".") == -1 ? '\n- email' : '';  
	error += f.your_request.value=='' ? '\n- message' : ''; 
	error += f.validator.value=='' ? '\n- text on graphic':''; 
	if (error != '')
	{
		alert('Please enter the following fields: \n ' +error);
	}   
	return error=='';
}  

function prepForms()
{
	for (var i=0; i<document.forms.length; i++)
	{
		var thisform = document.forms[i];
		thisform.onsubmit = function()
		{
			return checkForm(this);
		}
	}
}
                          
addLoadEvent(prepForms);