rem: var tagElements = document.getElementsByTagName(this.tabbableTags[j]); 
add: var tagElements = this.document.getElementsByTagName(this.tabbableTags[j]); 
context: 	disableTabs: function () {				this.tabbableTags = new Array("A","BUTTON","TEXTAREA","INPUT","IFRAME");		if (Wicket.Browser.isIE()) {			var win = Wicket.Window.current;						var i = 0;						this.tabIndexes = new Array();			for (var j = 0; j < this.tabbableTags.length; j++) {				var tagElements = document.getElementsByTagName(this.tabbableTags[j]);				for (var k = 0 ; k < tagElements.length; k++) {										// if this is not an iframe window and the element is child of window content,					// don't disable tab on it					if (win.isIframe() == true || this.isParent(tagElements[k], win.content) == false) {										this.tabIndexes[i] = tagElements[k].tabIndex;						tagElements[k].tabIndex="-1";					}					i++;				}			}		}	},
meta: 1204	/local1/tlutelli/issta_data/temp/all_js/javascript/2007_temp/2007/1204/de43bc2cae6b324eb459bfca9c4a4d244f285714/modal.js/clean/jdk-1.4/wicket-extensions/src/main/java/wicket/extensions/ajax/markup/html/modal/res/modal.js