Javascript Error throwing in Tree Tab of Main All Docs in Enterprise Manager 1.6.1

We had enterprise manager 1.3 version. After upgrading enterprise manager 1.3 to 1.6.1, when Tree Tab is viewed in Main/AllDocs page, following javascript exception are thrown.

URL : <xwiki-url>/xwiki/bin/view/Main/AllDocs?view=tree
1. 'findall(...)' is null or not an object – scriptaculous.js - Line 48 Char 5
2. Exception thrown and not caught – Line 11 Char 2
3. Object expected – Line 204 Char 2

There is faint occurance of scrollbar. Also image - skins/albatross/js/smartclient/skins/Enterprise/images/TreeGrid/opener_closed.gif on left side of text are not appearing.

This issue is occuring in Firefox, IE6 and IE7 browsers.