Failed to get the build source code: svn: report aborted

We cannot build some of our projects beause of this:

com.atlassian.bamboo.repository.RepositoryException: BAuA - BAuA Website
at com.atlassian.bamboo.repository.svn.SvnRepository.getChangesSinceLastBuild(SvnRepository.java:298)
at com.atlassian.bamboo.build.strategy.PollingBuildStrategy.requiresBuild(PollingBuildStrategy.java:126)
at com.atlassian.bamboo.build.DefaultBuildChangeDetector.checkIfBuildNeedsBuilding(DefaultBuildChangeDetector.java:166)
at com.atlassian.bamboo.build.DefaultBuildChangeDetector.doTask(DefaultBuildChangeDetector.java:114)
at com.atlassian.bamboo.build.DefaultBuildChangeDetector.run(DefaultBuildChangeDetector.java:77)
at edu.emory.mathcs.backport.java.util.concurrent.helpers.ThreadHelpers$1.run(ThreadHelpers.java:34)
at java.lang.Thread.run(Thread.java:595)
Caused by: org.tmatesoft.svn.core.SVNCancelException: svn: Error aborting report
svn: report abo rted
at org.tmatesoft.svn.core.internal.wc.SVNErrorManager.error(SVNErrorManager.java:58)
at org.tmatesoft.svn.core.internal.wc.admin.SVNReporter.report(SVNReporter.java:111)
at org.tmatesoft.svn.core.internal.io.dav.handlers.DAVEditorHandler.generateEditorRequest(DAVEditorHandler.java:81)
at org.tmatesoft.svn.core.internal.io.dav.DAVRepository.update(DAVRepository.java:590)
at org.tmatesoft.svn.core.wc.SVNUpdateClient.doUpdate(SVNUpdateClient.java:162)
at com.atlassian.bamboo.repository.svn.SvnRepository.update(SvnRepository.java:615)
at com.atlassian.bamboo.repository.svn.SvnRepository.getChangesSinceLastBuild(SvnRepository.java:275)

This is spreading to more projects now - maybe it's not a bug. What else could it be?

Could you please specify the SVN version used by Bamboo?