function validate_form_contact ()
{
	valid = true;  
		if(document.contact.name.value =="")
			{
				alert ( "Please fill in the 'Name' field" );
                valid = false;
			  
			}
		else if ( document.contact.email.value == "" )
			{
            	alert ( "Please fill in the 'Email' field" );
	            valid = false;
    	    }
		else if ( document.contact.message.value == "" )
			{
            	alert ( "Please write a message!" );
	            valid = false;
    	    }
        return valid;
}

function validate_form_guestbook ()
{
	valid = true;  
		if(document.guestbook.name.value =="")
			{
				alert ( "Please fill in the 'Name' field" );
                valid = false;
			  
			}
		else if ( document.guestbook.email.value == "" )
			{
            	alert ( "Please fill in the 'Email' field" );
	            valid = false;
    	    }
		else if ( document.guestbook.comment.value == "" )
			{
            	alert ( "Please write a message!" );
	            valid = false;
    	    }
        return valid;
}