function validate_form ( )
		{
			valid = true;
			if ( document.register_form.firstname.value == "" )
		    {
		    	alert ( "Please fill in your firstname." );
		        valid = false;
		    }
			if ( document.register_form.surname.value == "" )
		    {
		    	alert ( "Please fill in your surname." );
		        valid = false;
		    }
		   	if ( document.register_form.email.value == "" )
		    {
		    	alert ( "Please fill in your email address." );
		        valid = false;
		    }	
		   	if ( document.register_form.feedback.value == "" )
		    {
		    	alert ( "Please fill in your feedback." );
		        valid = false;
		    }			    		    			    	        	    
		   	return valid;
		}