Can't install 64-bit guest OS on 64-bit host

[evilflunky673]

I'm running Fedora 14 x86-64 and previously had VirtualBox OSE installed via RPM Fusion (so it stayed up to date), but currently have the Personal Use version installed. Both versions have run into the same primary issue: every time I try to install Fedora 12 x86-64 as a guest, the installer reports that it can't install a 64-bit OS on a 32-bit machine. Naturally, I installed the 64-bit version of VirtualBox; I got the RPM package from the VirtualBox.org site, specifically chose the 64-bit (AMD64) version, and installed VirtualBox-3.2-3.2.10_66523_fedora14-1.x86_64.rpm so I really don't get why I'm not getting the option to choose 64-bit versions of the operating systems in the guest configurations.

Any ideas of what's going on and how I can fix this issue? In another installation on a different machine and I believe under Windows Vista/7 I'm getting the ability to choose 64-bit guest OSes.

Thanks.

[Perryg]

Make sure that hardware virtualization is turned on in you PCs bios.