error enabling captcha ejabberd for windows

Hello i'm having a issue with captcha This is what i get when i enable it

=ERROR REPORT==== 2013-11-23 04:22:17 ===
C(<0.36.0>:gen_mod:75) : Problem starting the module mod_adhoc for host "localhost"
options: []
exit: {noproc,
{gen_server,call,
[ejabberd_iq_sup,
{start_child,["localhost",mod_adhoc,process_local_iq]},
infinity]}}

=ERROR REPORT==== 2013-11-23 04:22:17 ===
C(<0.36.0>:gen_mod:80) : ejabberd initialization was aborted because a module start failed.

ejabberd.cfg :

%%% CAPTCHA

%%
%% Full path to a script that generates the image.
%%
{captcha_cmd, "C:\\ejabberd\\lib\\ejabberd-2.1.11\\priv\\bin\\captcha.sh"}.

%%
%% Host part of the URL sent to the user.
%%
{captcha_host, "localhost:5280"}.

Please help me