The error was not in the osTicket.
I use the webmin (http://www.webmin.com(http://www.webmin.com) - a web administration system) to manage my server and I were testing the cronjob through the webmin, with the option run now. But, why I don't know, the IP address used when I use the run now is the address of the computer where I am accessing the webmim and not address of the server, for that the access was denied.
Looking at the log of when the cronjob turns automatically, I see that everything work.
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