--- a/lib/Ius/Dav/Htpasswd.pm	Thu Jul 07 14:18:54 2011 +0200
+++ b/lib/Ius/Dav/Htpasswd.pm	Tue Jul 12 10:58:31 2011 +0200
@@ -93,7 +93,7 @@
             unless defined $conf->{$_};
     }
 
-    $expiry = $conf->{expiry} unless defined $expiry;
+    $expiry = $conf->{expiry} unless defined $expiry and $expiry ne '';
     die 'Invalid input' unless validate $conf, $user, $expiry;
 
     my $at_cmd = "at now + " . 24 * 60 * $expiry . " minutes";