--- a/debian/postrm	Mon Nov 09 22:25:53 2015 +0100
+++ b/debian/postrm	Tue Nov 10 11:57:08 2015 +0100
@@ -19,25 +19,28 @@
 # the debian-policy package
 
 CONF=/etc/ca-certificates.conf
-CRT="schlittermann-ca.*\.crt"
+CRT="schlittermann"
+
+clean_conf() {
+
+    test -s $CONF || return
+
+    tmp=`mktemp`
+    grep -Fv "$CRT" $CONF >$tmp
+    cp $tmp $CONF
+    rm $tmp
+    return
+}
 
 case "$1" in
     purge)
-	TMP=`mktemp`
-	grep -v "$CRT" $CONF >$TMP
-	cp $TMP $CONF
-	rm $TMP
+	clean_conf
 	update-ca-certificates --fresh
     ;;
 
     remove|upgrade|failed-upgrade|abort-install|abort-upgrade|disappear)
-	if test -s "$CONF"; then
-	    tmp=`mktemp`
-	    grep -F -v 'schlittermann-ca.crt' $CONF >$tmp
-	    cp $tmp $CONF
-	    rm $tmp
-	fi
-	update-ca-certificates --fresh
+	clean_conf
+	test "$1" = upgrade || update-ca-certificates --fresh
     ;;
 
     *)