Problem with starting Back Track 5 R3 when CPU is set more than1 in VM

hi,
if set more than 1 CPU for Backtrack 5 R3 on virtual box i get this error:
http://i.imgur.com/wa0DF.png
if CPU is set at 1 all works, but extremly slow...
pls tell me what i must do that it works with more CPU´s


Kind regards,
zigouri

This is not a Backtrack bug, actually if I remember correctly this isn't a bug at all. The error that you are encountering means that your CPU does not have VT-x features, you can find a lot of documentation online on what that is, also I would suggest you report this to VirtualBox.