diff --git a/dspace-api/src/main/java/org/dspace/identifier/doi/DOIOrganiser.java b/dspace-api/src/main/java/org/dspace/identifier/doi/DOIOrganiser.java
index b03af68b42ab..0ee64f94b799 100644
--- a/dspace-api/src/main/java/org/dspace/identifier/doi/DOIOrganiser.java
+++ b/dspace-api/src/main/java/org/dspace/identifier/doi/DOIOrganiser.java
@@ -577,7 +577,8 @@ public void update(DOI doiRow) {
             }
         } catch (IdentifierException ex) {
             if (!(ex instanceof DOIIdentifierException)) {
-                LOG.error("It wasn't possible to register the identifier online. ", ex);
+                LOG.error("Registering DOI {} for object {}:  the registrar returned an error.",
+                        doiRow.getDoi(), dso.getID(), ex);
             }
 
             DOIIdentifierException doiIdentifierException = (DOIIdentifierException) ex;
diff --git a/dspace-api/src/main/java/org/dspace/identifier/doi/DataCiteConnector.java b/dspace-api/src/main/java/org/dspace/identifier/doi/DataCiteConnector.java
index 23af904f2c71..e56a82942369 100644
--- a/dspace-api/src/main/java/org/dspace/identifier/doi/DataCiteConnector.java
+++ b/dspace-api/src/main/java/org/dspace/identifier/doi/DataCiteConnector.java
@@ -461,6 +461,10 @@ public void reserveDOI(Context context, DSpaceObject dso, String doi)
                 log.warn("While reserving the DOI {}, we got a http status code "
                              + "{} and the message \"{}\".",
                         doi, Integer.toString(resp.statusCode), resp.getContent());
+                Format format = Format.getCompactFormat();
+                format.setEncoding("UTF-8");
+                XMLOutputter xout = new XMLOutputter(format);
+                log.info("We send the following XML:\n{}", xout.outputString(root));
                 throw new DOIIdentifierException("Unable to parse an answer from "
                                                      + "DataCite API. Please have a look into DSpace logs.",
                                                  DOIIdentifierException.BAD_ANSWER);
@@ -632,6 +636,14 @@ protected DataCiteResponse sendGetRequest(String doi, String path)
         return sendHttpRequest(httpget, doi);
     }
 
+    /**
+     * Send a DataCite metadata document to the registrar.
+     *
+     * @param doi identify the object.
+     * @param metadataRoot describe the object.  The root element of the document.
+     * @return the registrar's response.
+     * @throws DOIIdentifierException passed through.
+     */
     protected DataCiteResponse sendMetadataPostRequest(String doi, Element metadataRoot)
         throws DOIIdentifierException {
         Format format = Format.getCompactFormat();
@@ -640,6 +652,14 @@ protected DataCiteResponse sendMetadataPostRequest(String doi, Element metadataR
         return sendMetadataPostRequest(doi, xout.outputString(new Document(metadataRoot)));
     }
 
+    /**
+     * Send a DataCite metadata document to the registrar.
+     *
+     * @param doi identify the object.
+     * @param metadata describe the object.
+     * @return the registrar's response.
+     * @throws DOIIdentifierException passed through.
+     */
     protected DataCiteResponse sendMetadataPostRequest(String doi, String metadata)
         throws DOIIdentifierException {
         // post mds/metadata/
@@ -687,7 +707,7 @@ protected DataCiteResponse sendMetadataPostRequest(String doi, String metadata)
      *            properties such as request URI and method type.
      * @param doi DOI string to operate on
      * @return response from DataCite
-     * @throws DOIIdentifierException if DOI error
+     * @throws DOIIdentifierException if registrar returns an error.
      */
     protected DataCiteResponse sendHttpRequest(HttpUriRequest req, String doi)
         throws DOIIdentifierException {