Hi
The Acajoom CB plugin is available in two locations.
The first, on Joomlapolis, is out of date and causes the error described in this thread.
The second is available from the Acajoom site, but the link is buried in an obscure location.
The direct link is
www.ijoobi.com/help/acajoom/acajoom-download-area.html
I have just tested this version and it resolves the bug.
Regards
Brendon