If you want to use wicket's Ajax implementation with Opera Browser you have to do
to get it work.
Because of a Bug which is in all Opera Browsers before Version 9 Beta,
the ajax stuff will not work in Opera.
Opera 9.0 was made available for download in March 2007. Since then, many updates were released. By now, most Opera users should use a version not having the bug anymore.
Opera Ajax Wicket Strip wicket:id