从更新面板执行异步回发后保持滚动位置

I'm having some troubles with asp.net and update panel. The problem is, that every time partial postback occurs from update panel, page is scrolled back to top. On most of my pages this is not such a big problem, but on some pages can get quite long. Then, when user is on bottom of page, I show jQuery popup with I'm having some troubles with asp.net and updat