LCS-LIST doesn't propagate its TEST arg to subcalls. Fix: - (t (let ((lcs-1 (lcs-list list-1 (rest list-2))) - (lcs-2 (lcs-list (rest list-1) list-2))) + (t (let ((lcs-1 (lcs-list list-1 (rest list-2) :test test)) + (lcs-2 (lcs-list (rest list-1) list-2 :test test))) (wow, I diffed a diff tool!) Leslie -- LinkedIn Profile: http://www.linkedin.com/in/polzer Xing Profile: https://www.xing.com/profile/LeslieP_Polzer Blog: http://blog.viridian-project.de/