public virtual XmlAttribute Remove (XmlAttribute node) 

		{
			if (IsReadOnly)
				throw new ArgumentException ("This attribute collection is read-only.");
			if (node == null)
				throw new ArgumentException ("Specified node is null.");
			if (node.OwnerDocument != ownerDocument)
				throw new ArgumentException ("Specified node is in a different document.");
			if (node.OwnerElement != this.ownerElement)
				throw new ArgumentException ("The specified attribute is not contained in the element.");

			XmlAttribute retAttr = null;
			for (int i = 0; i < Count; i++) {
				XmlAttribute attr = (XmlAttribute) Nodes [i];
				if (attr == node) {
					retAttr = attr;
					break;
				}
			}

			if(retAttr != null) {
				ownerDocument.onNodeRemoving (node, ownerElement);
				base.RemoveNamedItem (retAttr.LocalName, retAttr.NamespaceURI);
				RemoveIdenticalAttribute (retAttr);
				ownerDocument.onNodeRemoved (node, ownerElement);
			}
			// If it is default, then directly create new attribute.
			DTDAttributeDefinition def = retAttr.GetAttributeDefinition ();
			if (def != null && def.DefaultValue != null) {
				XmlAttribute attr = ownerDocument.CreateAttribute (
					retAttr.Prefix, retAttr.LocalName, retAttr.NamespaceURI);
				attr.Value = def.DefaultValue;
				attr.SetDefault ();
				this.SetNamedItem (attr);
			}
			retAttr.AttributeOwnerElement = null;
			return retAttr;
		}