[mer-general] failed to add Qt version

[Nicola De Filippo]

Hi,
i'm installing mer-sdk with virtual-box 
(https://wiki.merproject.org/wiki/Platform_SDK_on_VirtualBox) but 
as i add the targert (nemo_n9_min in /srv/mer/targets) in qtcreator-mer i have 
this error "failed to add Qt version".

have you  any suggestions?
         Thanks
               Nicola