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A versão 1.5.16 (25 Abril 2010) contem 2 bugs sérios que afetarão seu site se você usa PHP anterior a 5.2 ou se você tem o parâmetro Session Handler setado para "None" na Configuração Global.IMPORTANT UPDATE EFFECTIVE 25 APRIL 2010: Version 1.5.16 contains two serious bugs that will affect your site if you use a version of PHP prior to 5.2 or if you have the Session Handler parameter set to None in Global Configuration. To correct these issues, version 1.5.17 is scheduled to be released on 27 April 2010. If you haven't already upgraded to version 1.5.16, you may wish to wait for version 1.5.17 instead.