From: Raphael Geissert <geissert@debian.org>

--- ifscheme-1.7.orig/ifscheme
+++ ifscheme-1.7/ifscheme
@@ -107,7 +107,7 @@
 		# Second, extract from the state file any real interface
 		# which liface either match the mapping above or is
 		# appened by the old scheme name.
-		active_ifaces=$(grep -F -- "-$oldscheme"$'\n'"$old_mappings" $IFSTATE | cut -d = -f 1)
+		active_ifaces=$(grep -F -- "$(printf -- "-%s\n%s" "$oldscheme" "$old_mappings")" $IFSTATE | cut -d = -f 1)
 
 		# Now, restart all those interfaces
 		for iface in $active_ifaces ; do