diff --git a/applets/pbot-vm/host/lib/Languages/_default.pm b/applets/pbot-vm/host/lib/Languages/_default.pm
index 60276ba8..6de06281 100755
--- a/applets/pbot-vm/host/lib/Languages/_default.pm
+++ b/applets/pbot-vm/host/lib/Languages/_default.pm
@@ -115,7 +115,7 @@ sub process_cmdline_options($self) {
     $self->{code} = $code;
 }
 
-sub add_option($self, $option, $value) {
+sub add_option($self, $option, $value = '') {
     $self->{options_order} //= [];
     $self->{options}->{$option} = $value;
     push @{$self->{options_order}}, $option;