Message Oracle ORA-53008 - The tag value is not a registered schema.

ERROR	The tag value is not a registered schema.
CAUSE	The schema URL specified by the value of the tag was not a registered Oracle XML DB schema.
ACTION	Specify a registered schema URL value. See the ALL_XML_SCHEMAS view for a list of registered schemas. See the Oracle XML DB Developerss Guide for information about registering schemas. See the Oracle Multimedia documentation for information about the mapping document schema (ordcmmp.xsd).