sieve vacation reposnse gives no response even after end of days specified

[ram]

I have a default cyrus installation with cyrus-imapd-2.3 on centos 5 
People use sieve to set their vacation responses 

As per the configuration no response is sent for 1 day 
---------
cat  /usr/sieve/i/it/default.script

require "vacation";
# Vacation
vacation :days 1 :addresses "it at example.com" "this is a vacation
response";
------------------


The first vacation response seems to go perfectly fine , but even after
1 day the response is not sent again

What could be the issue ? how do I debug this ?