svn+ssh fails with "network data doesn't match template, expected (, read ? (65535)"

I get this error, running Idea 5.0.1 on WinXP. I use svn+ssh, and the command line svn client (1.2.1) works fine.

If noone knows this specific answer, can someone tell me how to get the subversion code to output full debugging data to a log someplace so I can pursue further?

Thanks.

org.tmatesoft.svn.core.SVNException: network data doesn't match template, expected (, read ? (65535)
at org.tmatesoft.svn.core.internal.io.svn.SVNReader.readChar(SVNReader.java:579)
at org.tmatesoft.svn.core.internal.io.svn.SVNReader.parse(SVNReader.java:260)
at org.tmatesoft.svn.core.internal.io.svn.SVNConnection.read(SVNConnection.java:196)
at org.tmatesoft.svn.core.internal.io.svn.SVNConnection.handshake(SVNConnection.java:64)
at org.tmatesoft.svn.core.internal.io.svn.SVNConnection.open(SVNConnection.java:56)
at org.tmatesoft.svn.core.internal.io.svn.SVNRepositoryImpl.openConnection(SVNRepositoryImpl.java:657)
at org.tmatesoft.svn.core.internal.io.svn.SVNRepositoryImpl.getLatestRevision(SVNRepositoryImpl.java:72)
at org.tmatesoft.svn.core.wc.SVNBasicClient.getRevisionNumber(SVNBasicClient.java:198)
at org.tmatesoft.svn.core.wc.SVNLogClient.doLog(SVNLogClient.java:166)
at org.jetbrains.idea.svn.history.SvnVersionsProvider.getFilteredVersions(SvnVersionsProvider.java:89)
at com.intellij.openapi.vcs.versionBrowser.ChangesBrowser$6.run(ChangesBrowser.java:5)
at com.intellij.openapi.progress.impl.ProgressManagerImpl.runProcess(ProgressManagerImpl.java:16)
at com.intellij.openapi.application.impl.ApplicationImpl$1MyThread.run(ApplicationImpl.java:13)