Grails : UnknownHostException at startup

I had the following error when starting Grails project :

| Error 2014-03-08 20:54:41,199 [localhost-startStop-1] ERROR [localhost].[/toolprod]  - StandardWrapper.Throwable
Message: IO Exception: "java.net.UnknownHostException: blopux: blopux: Nom ou service inconnu" [90028-173]

To solve my problem, I had the hostname in /etc/hosts :

127.0.0.1   blopux        localhost