1、需要对IE6支持的话，只能使用jQuery UI 1.9.2，目前官网定制页只有1.9.2会支持IE6，
jQuery UI Upgrade Guide（升级指南）中指出
Removed support for IE6
IE6 usage has dropped to a low enough point that jQuery UI no longer finds it necessary to support. As of 1.10.0, some portions of jQuery UI may not work properly in IE6. If you need to continue to support IE6, use the latest jQuery UI 1.9 release.
jQuery UI 1.11 Upgrade Guide
Discontinued IE7 Support
As of this release we are no longer accepting bug reports for IE7 issues. We have also removed IE7 from our testing infrastructure. The IE7 workarounds are still present in the code, but we will remove them for jQuery UI 1.12.
2、部分组件只在服务端生效，目前用过的服务端生效的有：resizable、slider、