ISVNAuthentication provider did not provide credentials (no variables or externals)

[Arthur Ramsey]

Jenkins: 1.596.2 (LTS)
Subversion Plug-in: 2.5
Credentials Plugin: 1.22
Subversion Server: 1.8
Subversion Working Copy: 1.7

Tagging https://svn.mediture.com/root/trunk (rev.100666) to https://svn.mediture.com/root/tags/LIFEconnect-179
ERROR: Failed to tag
org.tmatesoft.svn.core.SVNCancelException: svn: E200015: E200015: ISVNAuthentication provider did not provide credentials; HTTP authorization cancelled.
svn: E200015: ISVNAuthentication provider did not provide credentials; HTTP authorization cancelled.
    at org.tmatesoft.svn.core.internal.wc.SVNErrorManager.error(SVNErrorManager.java:60)
    at org.tmatesoft.svn.core.internal.wc.SVNErrorManager.error(SVNErrorManager.java:51)
    at org.tmatesoft.svn.core.internal.io.dav.http.HTTPConnection.request(HTTPConnection.java:759)
    at org.tmatesoft.svn.core.internal.io.dav.http.HTTPConnection.request(HTTPConnection.java:371)
    at org.tmatesoft.svn.core.internal.io.dav.http.HTTPConnection.request(HTTPConnection.java:359)
    at org.tmatesoft.svn.core.internal.io.dav.DAVConnection.performHttpRequest(DAVConnection.java:710)
    at org.tmatesoft.svn.core.internal.io.dav.DAVConnection.exchangeCapabilities(DAVConnection.java:627)
    at org.tmatesoft.svn.core.internal.io.dav.DAVConnection.open(DAVConnection.java:102)
    at org.tmatesoft.svn.core.internal.io.dav.DAVRepository.openConnection(DAVRepository.java:1032)
    at org.tmatesoft.svn.core.internal.io.dav.DAVRepository.getRepositoryRoot(DAVRepository.java:127)
    at org.tmatesoft.svn.core.internal.wc.SVNCopyDriver.copyReposToRepos(SVNCopyDriver.java:194)
    at org.tmatesoft.svn.core.internal.wc.SVNCopyDriver.setupCopy(SVNCopyDriver.java:627)
    at org.tmatesoft.svn.core.internal.wc16.SVNCopyClient16.doCopy(SVNCopyClient16.java:440)
    at org.tmatesoft.svn.core.internal.wc2.remote.SvnNgReposToReposCopy.run(SvnNgReposToReposCopy.java:65)
    at org.tmatesoft.svn.core.internal.wc2.remote.SvnNgReposToReposCopy.run(SvnNgReposToReposCopy.java:23)
    at org.tmatesoft.svn.core.internal.wc2.SvnOperationRunner.run(SvnOperationRunner.java:21)
    at org.tmatesoft.svn.core.wc2.SvnOperationFactory.run(SvnOperationFactory.java:1259)
    at org.tmatesoft.svn.core.wc2.SvnOperation.run(SvnOperation.java:294)
    at org.tmatesoft.svn.core.wc2.SvnRemoteCopy.run(SvnRemoteCopy.java:227)
    at org.tmatesoft.svn.core.wc.SVNCopyClient.doCopy(SVNCopyClient.java:581)
    at hudson.scm.SubversionTagAction$TagWorkerThread.perform(SubversionTagAction.java:307)
    at hudson.model.TaskThread.run(TaskThread.java:127)
Caused by: org.tmatesoft.svn.core.SVNCancelException: svn: E200015: ISVNAuthentication provider did not provide credentials; HTTP authorization cancelled.
    at org.tmatesoft.svn.core.internal.io.dav.http.HTTPConnection.request(HTTPConnection.java:689)
    ... 19 more

I see a request hit apache (svn host), but no request sent to LDAP server.  We use basic authentication with an LDAP authentication provider.  We don't use variables in the URI or externals.  I tried downgrading the subversion plugin, but get a similar error.  I also tried deleting $JENKINS_HOME/.subversion.  I also tried the SSLv3 only hack without success.  I tried global and personal credentials, but ultimately want to use personal credentials (it would be great if the jenkins ui login passed through to svn).