vagrant up 后出现下列错误提示

 Failed to mount folders in Linux guest. This is usually because
the "vboxsf" file system is not available. Please verify that
the guest additions are properly installed in the guest and
can work properly. The command attempted was:

mount -t vboxsf -o uid=`id -u vagrant`,gid=`getent group vagrant | cut -d: -f3` vagrant /vagrant
mount -t vboxsf -o uid=`id -u vagrant`,gid=`id -g vagrant` vagrant /vagrant

已经 Google 了各种，使用了vagrant-vbguest，已经没有解决，把 virtualbox 从 4.3.14降到了4.2.26，还是会出现这个问题
gust 里的系统是 ubuntu12.04，也试过了14.04，host 是 OS X 10.09
请问这个怎么解决？

update:
mount.vboxsf -o uid=`id -u vagrant`,gid=`getent group vagrant | cut -d: -f3` vagrant /vagrant
手动可以挂载