You might have deployed a web service [a BPEL process lets say] onto the container, and would have registered the service with the Oracle Web Services Manager Gateway.
If you are trying to create a partnerlink in another BPEL Process that wishes to invoke this BPEL Process, you might receive an error pertaining to "invalid XSD" or "malformed XSD" that has been imported into the original Process. The issue occurs if the WSDL refers to the XSD using a relative location URL.
For fixing this issue, you would need to copy the XSD into the $ORACLE_HOME/owsm/config/gateway/services directory, and re-deploy the gateway.