Hi Mario,
it could be one of several things that come to mind:
1) client will be available only through SAP HANA Enterprise Cloud / Cloud Appliance Library
2) the 'usual' download site is undergoing maintenance and we will see ver 90 or 91 there shortly
3) neither
you may still be able to upload the client through your SAP login, but i haven't checked recently and don't have the exact link for you.
wishing you a happy hana experience,
greg