I discovered a problem that occurs when using Groovy 2.2.x or later I created a project to illustrate the problem at https://github.com/corneil/groovy-grape-ivy
It seems that in some cases the artifacts are ignored and derived from the name of the module. The first dependency encountered reports a problem when try to load artifacts after the artifacts of the child dependencies was retrieved. It is not specific to a dependency because changing to order of the Grape call shows that it always messes up the artifacts of the first on encountered.