Make sure that the correct value is retreived for options that have n…

…o 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 ) {