--- orig/debconf-force-selections
+++ mod/debconf-force-selections
@@ -26,14 +26,7 @@
 set -e
 
 . /lib/elho/shell-tools
-
-package_installed ()
-{
-    local package="$1"
-
-    dpkg-query --showformat='${Status}\n' --show "${package}" 2>/dev/null \
-	| grep --quiet '^[^[:space:]]\+[[:space:]]\+ok[[:space:]]\+\(installed\|triggers-pending\)$'
-}
+. /lib/elho/deb-tools
 
 preseed_to_configdb ()
 {
