diff --git a/rmate b/rmate
index ce696b2..3379d42 100755
--- a/rmate
+++ b/rmate
@@ -170,6 +170,7 @@ function canonicalize {
     echo "$result"
 }
 
+shopt -s extglob
 while [[ "$1" != "" ]]; do
     case $1 in
         -)
@@ -222,7 +223,7 @@ while [[ "$1" != "" ]]; do
             showusage
             exit 0
             ;;
-        +[0-9][0-9]*)
+        \++([0-9]))
             selections+=(${1:1})
             ;;
         *)
@@ -237,6 +238,7 @@ while [[ "$1" != "" ]]; do
 
     shift
 done
+shopt -u extglob
 
 if [[ "$host" = "auto" && "$SSH_CONNECTION" != "" ]]; then
     host=${SSH_CONNECTION%% *}