[xwiki-users] not quite seamless upgrade

I just upgraded our relatively small xwiki instance from 3.0.0 to 3.1.1 I did the upgrade by setting up a new host with tomcat6 etc, putting the .war file in place, restarting tomcat to automatically expand the .war and then merging the xwiki.cfg xwiki.properties & hibernate.cfg.xml files All storage is in the database (Oracle) and the only skin in use is Colibri I then uploaded the current Administration.xar apart from the 5 pages remarked on in the instructions. All the data is there, but I have a slight problem, there top bar of the wiki (http://extensions.xwiki.org/xwiki/bin/view/Extension/Colibri+Skin where the Add Wiki Space etc "buttons are) is not there, the text is, but without anything to Any suggestions as to what I've managed to mangle or need to reset would be appreciated. Cheers