Lasso, single tool

[Kytt]

Lasso tool is working only in 3D window, Topview its working as Single and Ctrl key does not deselect faces in 3D or Topview window.
Single tool is working fine in both windows but i can only deselect faces in 3D window.
Is it bug or should it work like that?

Vista 32bit
core2 duo
nvidia 7900GTO
2GB RAM
latest drivers, .NET, directx