[Serg_pnz]

я так сделал

jQuery.ajax({
	    type: 'POST',
		url: 'ajaxform/captchaimg.php',
		beforeSend: function(){
			$('#spanimg').html('<img id="imgcode" src="ajaxform/loadinfo.gif">');
		},
		success: function(msg){
			$('#spanimg').html(msg);
	    }