--- prog/fiaif-update.orig
+++ prog/fiaif-update
@@ -89,7 +89,7 @@
     echo "New version of $(basename ${ORIG_FILE}) found."
     diff ${DIFF_OPTIONS} ${ORIG_FILE} ${NEW_FILE}
     if (( VERBOSE == 1 )); then
-	while [[ "${ANS}" != @(Y|y|N|n) ]]; do
+	while [[ ("${ANS}" !=  "Y") && ("${ANS}" !=  "y") && ("${ANS}" !=  "N") && ("${ANS}" !=  "n") ]]; do
 	    read -p "Update $(basename ${ORIG_FILE}) to version ${NEW_VERSION} (y|n)" ANS
 	done
     else