Server returned malformed response: Content is not allowed in prolog

I get the following error when trying to create a review upon commit from Intellij IDEA, seems like crucible sends malformed xml:

com.atlassian.theplugin.commons.remoteapi.RemoteApiException: http://localhost:8060: Server returned malformed response
at com.atlassian.theplugin.commons.crucible.api.rest.CrucibleSessionImpl.throwMalformedResponseReturned(CrucibleSessionImpl.java:1609)
at com.atlassian.theplugin.commons.crucible.api.rest.CrucibleSessionImpl.createReviewFromRevision(CrucibleSessionImpl.java:1347)
at com.atlassian.theplugin.commons.crucible.CrucibleServerFacadeImpl.createReviewFromRevision(CrucibleServerFacadeImpl.java:219)
at com.atlassian.connector.intellij.crucible.IntelliJCrucibleServerFacade.createReviewFromRevision(IntelliJCrucibleServerFacade.java:232)
at com.atlassian.theplugin.idea.crucible.AbstractCrucibleCreatePostCommitReviewForm.createReviewImpl(AbstractCrucibleCreatePostCommitReviewForm.java:69)
at com.atlassian.theplugin.idea.crucible.CrucibleCreatePostCommitReviewDelayedForm.createReview(CrucibleCreatePostCommitReviewDelayedForm.java:81)
at com.atlassian.theplugin.idea.crucible.CrucibleReviewCreateForm$9.run(CrucibleReviewCreateForm.java:856)
at com.intellij.openapi.progress.impl.ProgressManagerImpl$TaskRunnable.run(ProgressManagerImpl.java:428)
at com.intellij.openapi.progress.impl.ProgressManagerImpl$2.run(ProgressManagerImpl.java:198)
at com.intellij.openapi.progress.impl.ProgressManagerImpl.executeProcessUnderProgress(ProgressManagerImpl.java:223)
at com.intellij.openapi.progress.impl.ProgressManagerImpl.runProcess(ProgressManagerImpl.java:189)
at com.intellij.openapi.progress.impl.ProgressManagerImpl$6.run(ProgressManagerImpl.java:343)
at com.intellij.openapi.application.impl.ApplicationImpl$5.run(ApplicationImpl.java:331)
at java.util.concurrent.Executors$RunnableAdapter.call(Executors.java:441)
at java.util.concurrent.FutureTask$Sync.innerRun(FutureTask.java:303)
at java.util.concurrent.FutureTask.run(FutureTask.java:138)
at java.util.concurrent.ThreadPoolExecutor$Worker.runTask(ThreadPoolExecutor.java:886)
at java.util.concurrent.ThreadPoolExecutor$Worker.run(ThreadPoolExecutor.java:908)
at java.lang.Thread.run(Thread.java:619)
at com.intellij.openapi.application.impl.ApplicationImpl$1$1.run(ApplicationImpl.java:125)
Caused by: org.jdom.input.JDOMParseException: Error on line 1: Content is not allowed in prolog.
at org.jdom.input.SAXBuilder.build(SAXBuilder.java:504)
at org.jdom.input.SAXBuilder.build(SAXBuilder.java:807)
at com.atlassian.theplugin.commons.remoteapi.rest.AbstractHttpSession.retrievePostResponseInternalImpl(AbstractHttpSession.java:410)
at com.atlassian.theplugin.commons.remoteapi.rest.AbstractHttpSession.retrievePostResponseInternal(AbstractHttpSession.java:343)
at com.atlassian.theplugin.commons.remoteapi.rest.AbstractHttpSession.retrievePostResponse(AbstractHttpSession.java:334)
at com.atlassian.theplugin.commons.remoteapi.rest.AbstractHttpSession.retrievePostResponse(AbstractHttpSession.java:329)
at com.atlassian.theplugin.commons.remoteapi.rest.AbstractHttpSession.retrievePostResponse(AbstractHttpSession.java:322)
at com.atlassian.theplugin.commons.crucible.api.rest.CrucibleSessionImpl.createReviewFromRevision(CrucibleSessionImpl.java:1335)
... 18 more
Caused by: org.xml.sax.SAXParseException: Content is not allowed in prolog.
at org.apache.xerces.util.ErrorHandlerWrapper.createSAXParseException(Unknown Source)
at org.apache.xerces.util.ErrorHandlerWrapper.fatalError(Unknown Source)
at org.apache.xerces.impl.XMLErrorReporter.reportError(Unknown Source)
at org.apache.xerces.impl.XMLErrorReporter.reportError(Unknown Source)
at org.apache.xerces.impl.XMLErrorReporter.reportError(Unknown Source)
at org.apache.xerces.impl.XMLScanner.reportFatalError(Unknown Source)
at org.apache.xerces.impl.XMLDocumentScannerImpl$PrologDispatcher.dispatch(Unknown Source)
at org.apache.xerces.impl.XMLDocumentFragmentScannerImpl.scanDocument(Unknown Source)
at org.apache.xerces.parsers.XML11Configuration.parse(Unknown Source)
at org.apache.xerces.parsers.XML11Configuration.parse(Unknown Source)
at org.apache.xerces.parsers.XMLParser.parse(Unknown Source)
at org.apache.xerces.parsers.AbstractSAXParser.parse(Unknown Source)
at org.apache.xerces.jaxp.SAXParserImpl$JAXPSAXParser.parse(Unknown Source)
at org.jdom.input.SAXBuilder.build(SAXBuilder.java:489)
... 25 more