rem: var position = {left: obj.x - this.getComputedStyle('margin-left').toInt() || 0, top: obj.y - this.getComputedStyle('margin-top').toInt() || 0}; 
add: var position = { left: obj.x - (this.getComputedStyle('margin-left').toInt() || 0), top: obj.y - (this.getComputedStyle('margin-top').toInt() || 0) }; 
context: 	computePosition: function(obj, client){		var scroll, el = this;		var position = {left: obj.x - this.getComputedStyle('margin-left').toInt() || 0, top: obj.y - this.getComputedStyle('margin-top').toInt() || 0};		if (client){			scroll = Dimensions.getScroll(Dimensions.getOffsetParent(this));			position.left += scroll.x;			position.top += scroll.y;		}		if (Browser.Engine.presto){			while ((el = el.parentNode) && el != this.offsetParent){				scroll = Dimensions.getScroll(el);				position.left += scroll.x;				position.top += scroll.y;			}		}		return position;	},
meta: 6317	/local1/tlutelli/issta_data/temp/all_js/javascript/2007_temp/2007/6317/ccf4ea8e2de2f6d863c3e44f5b375ea607020d83/Dimensions.js/clean/Source/Utilities/Dimensions.js