Oracle Message NNC-00425 - meta-data violation

ERRORmeta-data violation
CAUSEA caller issued a name server modification request and that request cannot be processed because it would violate data type meta-data constraints.
ACTIONNot normally visible to the user, except when using the name server control program. If the error occurs when using the control program, examine the meta-data constraints for the data type being operated upon and dont violate them. Examples of typical constraint violations are attempts to add a new data item to a name which already contains alias information, or attempts to add alias information to a name which already contains other data, or attempts to replace a data item with another item that has the wrong syntax. If the error occurs outside the control program, turn on tracing and re-execute the failing operation. If the error persists, contact Worldwide Customer Support.