Make sure that the correct value is retreived for options that have no value...

Make sure that the correct value is retreived for options that have no value specified, in IE 6. Continues to fix #5697.

src/attributes.js

@@ -164,7 +164,9 @@ jQuery.fn.extend({
 				var values = jQuery.makeArray(val);
 
 				jQuery( "option", this ).each(function() {
-					this.selected = jQuery.inArray( this.value, values ) >= 0;
+					// IE 6 will return "" for the value if one isn't specified, instead of the text
+					var node = this.getAttributeNode("value");
+					this.selected = jQuery.inArray( node && node.specified ? node.value : this.value || this.text, values ) >= 0;
 				});
 
 				if ( !values.length ) {