[Koha] Convert from koha 1.2.3 to koha 3.00.00

Hi to all I need help, i have koha 1.2.3 on machine anf its ok i want to upgrade form koha 1.2.3 to koha 3.00 but i know must be first convert it from 1.2.3 to koha 2 and second to koha 3.00 please if any body have idea about steps to convert it send me it thnks _________________________________________________________________ More than messages–check out the rest of the Windows Live™. http://www.microsoft.com/windows/windowslive/