I know of three open source UDDI implementations:
Plus these are open source UDDI client projects:
None of these projects is particularly vibrant. The UDDI implementations are what I refer to as "vanilla" implementations of the UDDI specification. They provide no additional tools, features, or value. The client libraries don't do much for you to abstract the complexity of the UDDI data model. So the short answer is, "no, there are not any good open source UDDI tools."
This was first published in July 2008