OSX is my host OS
I have windows xp and Ubuntu 10.10 on guest OS. They both work great. When I eject USB flash drive from host OS, it appears in windows guest OS but it does not appear in Ubuntu Guest OS.
I never run both guest OS at the same time. its always either or.
I am running, VM virtualbox 4.1.10 and installed latest guest additions and also installed VM virtualbox extension pack. Thanks for your help