Call to undefined function views_build_view()

http://www.strictlyreading.co.uk/page/past-reading-festivals/reading-fes... and I get the error: Fatal error: Call to undefined function views_build_view() in /home/janusz/public_html/includes/common.inc(1547) : eval()'d code on line 5

I also notice my old views were not saved/imported. Have I missed something major?

Thanks.