mod_http_offline not working

Hi,

I have done with mod_http_offline module but its not running properly. I will showing below error in error log

c(<0.37.0>:gen_mod:75) : Problem starting the module mod_http_offline for host "localhost"
options: [{access_max_user_messages,max_user_offline_messages}]
error: function_clause

PLease help me out....