"Show all" for posts in the topic

At the end of first page of topic user could see button/link "Show all".
Button "Show all" is shown only if topic has pages.
After click on it, posts from next pages are displaying after last post on current page.
Button "Show all" changed its caption to "Show pages". Clicking on it now get back view of topic to paging style.

http://jtalks.org/pages/viewpage.action?pageId=9994400