Is it possible to debug VS2010 .NET 4.0 project in VS2008?

Sure, i can't open VS2010 solution in VS2008. I try to attach remote debugger from VS2008 to project of VS2010, but it fails. Can i attach debugger from VS 2008 to .NET 4.0 application built in VS2010?

Assume i can't install VS20开发者_StackOverflow中文版10 on this machine. Universe existence depends on this question...

Any help will be appreciated!

---

When I try to attach a .NET 4 app from VS2008, the process appears in the process list - but it is grayed out. So I think it is not possible - which would be reasonable.