How to change admin route prefix for typus on rails3.1?

I want to change admin route path for typus开发者_开发问答 on rails3.1.

[Before] localhost:3000/admin

[After] localhost:3000/example

3-1-unstable version implemented?

https://github.com/typus/typus/issues/120#issuecomment-651711

How to coding? route.rb? mountable?

Thanks.

The typus project reports that this is "not supported" in the github issue queue