code: public void setSystemMessageSourceUuid(SIBUuid8 value) {
          if (TraceComponent.isAnyTracingEnabled() && tc.isEntryEnabled())
              SibTr.entry(this, tc, "setSystemMessageSourceUuid", value);
          // Clear the cached MessageHandle
          cachedMessageHandle = null;
          // Set the value into the message itself
          if (value != null) {
              jmo.setField(JsHdrAccess.SYSTEMMESSAGESOURCEUUID, value.toByteArray());
          }
          else {
              jmo.setField(JsHdrAccess.SYSTEMMESSAGESOURCEUUID, null);
          }
          if (TraceComponent.isAnyTracingEnabled() && tc.isEntryEnabled())
              SibTr.exit(this, tc, "setSystemMessageSourceUuid");
      }
docs: /*
  Set the value of the SystemMessageSourceUuid field in the message header.
  
  Javadoc description supplied by JsMessage interface.