Problem with db create

Hi,
When I do the book’s tutorial I have an issue.

lotus db create
WARN: Unresolved specs during Gem::Specification.reset:
rack (>= 1.0, >= 1.0.0, ~> 1.5)
WARN: Clearing out unresolved specs.
Please report a bug if this causes problems.

Do you have a solution ?

Thanks

It was a rack conflict .All is ok now

I still have this issue. Should I update something?

Yes I have deleted the old rack with gem uninstall rack .