Memory usage for VirtualBox incorrect in host OS task manager

[NG]

I have 1.5GB of RAM allocated to my Windows Vista 32-bit VM (on a Windows Vista 64-bit host). When VirtualBox starts up, it immediately "consumes" the 1.5GB of RAM as evidenced by the memory usage in the "Performance" tab of task manager on the host OS. However, the VirtualBox processes in task manager don't show this memory usage. I'd think one of the VirtualBox processes should show the correct memory being used by the process.