how to ignore missing metadata?

[Limbic System]

We have a custom maven1-style repository with several years' worth of legacy
artifacts from our organization.  I seem to be able to resolve artifacts
from this repo, but my resolve/retrieve tasks always fail because there is
no pom/ivy.xml metadata for the artifacts.  Is there a way to ask ivy to
ignore missing metadata?  I've tried setting transitive="false" as well as
validate="false" to no good effect.
Thanks for your help,
L