diff --git a/handlers/dup.in b/handlers/dup.in
index c338e47dcb1eda443c9fa929e8fa7a8cffff6c67..9c38de3b50441292bac2646c3019c132ad723fcb 100644
--- a/handlers/dup.in
+++ b/handlers/dup.in
@@ -313,7 +313,7 @@ fi
 if [ "$keep" != "yes" ]; then
    debug "executing duplicity remove-older-than"
    debug "$nice $execstr_precmd duplicity remove-older-than $keep --force $execstr_options $execstr_serverpart"
-   if [ ! $test ]; then
+   if [ $test = 0 ]; then
       export PASSPHRASE=$password
       export SIGN_PASSPHRASE=$signpassword
       export FTP_PASSWORD=$ftp_password