connecting artifactory repository to nexus

Question

I'm in an organization with multiple development efforts existing in parallel. My project is using Nexus to manage our Maven repository, and there's another group using Artifactory for their Maven needs. I'm trying to set up a proxy that points to their repository for snapshots, and am running into problems. When I try to configure the proxy, the status comes up as "Remote Automatically Blocked and Unavailable."

I'm not having troubles with any of the other proxies, so I think that my Nexus setup is basically okay. Does anyone know of additional Nexus configuration needed to point to an Artifactory repository? Conversely, is there some Artifactory tweaking needed to allow its use by Nexus?

Thank in advance!