function change(elem){
			//pobiera wysokosc z arkuszu styli
            var mysheet = document.styleSheets[0]
            var myrules=mysheet.cssRules? mysheet.cssRules: mysheet.rules
            for (i=0; i<myrules.length; i++){
                if(myrules[i].selectorText.toLowerCase() == "p.txt_height"){
                    targetrule=myrules[i]
                break;
                }
            }
            var firstrule=mysheet.cssRules? mysheet.cssRules[i]: mysheet.rules[i]
            var height = parseInt((firstrule.style.height).replace('px',''));
			//----------------

			var txt = $('#txt_'+elem);
			var button = $('#showhide_'+elem);
            var h = parseInt(txt.css('height').replace('px',''));

			if(h>height){
				txt.attr('style', 'height:40px;');
                button.text('rozwi\u0144');
            }
            else {
//				txt.css("height", "auto");/

				txt.animate({height: "100%"},500 );
				var x = parseInt(txt.css('height').replace('px',''));
				if(x <40){
					txt.attr('style', 'height:40px;');
				}
				if(x > 40){
					button.text('zwi\u0144');
				}            
            }
        }