Hi guys
This is actually quiet easy to install. This is how I done it for any one who is interested.
1) Download VirtualBox 1.5.0 from here
http://www.virtualbox.org/wiki/Downloads*** Choose the binary for "All distributions" ***********
32-bit download here
http://www.virtualbox.org/download/1.5. ... ux_x86.run64-bit download here
http://www.virtualbox.org/download/1.5. ... _amd64.run2) Right click on the downloaded "run" file and change it to an executable.
3) Open up a konsole and change directory to where you downloaded the "run" file.
4) Type "
su" and enter root password
5) Remove old
vboxdrv kernel module from memory (if it's loaded) by typing "
rmmod vboxdrv" (without quotes).
6) Un-emerge your existing Virtualbox. E.g emerge -c virtualbox-bin virtualbox-modules
7) In konsole type "
./VirtualBox_1.5.0_Linux_amd64.run install /opt/Virtualbox" (without quotes and replace with your downloaded file name)

A start icon should be placed under kmenu->applications->system->Virtual Machine(virtualbox)
note: if it comes up with an error when you run it then try to reboot first.
All the best
Dave
p.s. Here's a list of changes
http://www.virtualbox.org/wiki/ChangelogIt now supports 64-bit windows as guest OS.