Hi, Our kdl_1.0 package depends on eigen. Before we were just specifying a dependency on the eigen package provided in the geometry stack as: Alternatively we can also depend on an external eigen package (e.g. the ubuntu package libeigen2-dev) as: Now I want to adapt the manifest so that either the ROS package OR the external package are needed as a dependency. Does the manifest allow this kind of OR statements? Tinne