Thank you! I no longer work on a project that uses TFS, but I will pass this on to some of my colleagues on my old team.

Fixed by switching to TFS SDK for Java and no longer parsing the output of the CLC.

On further investigation, the commit message is the issue:

I am using git-tf to send from my git repo to tfs. I had --metadata set to true. This converts your git commit messages like "blah" to something like:

"Commit abcdef (Tue May 21 14:19:15 2013 +1000)
Author: David Clark <david.clark@[redacted].com>
Committer: David Clark <david.clark@[redacted].com>
-----------------------------------------------------------------
blah
"

Which is causing the parse error in the polling. (Due to "---" it seems).

BTW: for anyone with a repo in this state you can fix it by:

1. git tf configure --no-metadata
2. push a change OR using team explorer, edit the last change set comment to not contain "---"

I am having the same issue, however the commit message is not the problem.
Also: The TFS server poller fails forever after a tfs checkin. However, if I manually run the build it will fail once, then work on the next try.

Here is the log:

Started on May 3, 2013 5:38:07 PM
[workspace] $ /Applications/TEE-CLC-10.0.0/tf history "$/Hotel Search iPhone" -noprompt -version:D2013-05-03T07:32:40Z~D2013-05-03T07:38:08Z -recursive -format:detailed -server:http://tfs2012:8080/tfs ********
Changeset: 40495
User: AAA\DavidC
Date: May 3, 2013 5:37:50 PM

Comment:
  Commit 853906c (Fri May 03 17:37:43 2013 +1000)
Author: David Clark <david.clark@hotelscombined.com>
Committer: David Clark <david.clark@hotelscombined.com>
-----------------------------------------------------------------
    version bump to test CI



Items:
  edit $/Hotel Search iPhone/HCWeb/HCWeb-Info.plist

FATAL: Parse error. Unable to find an item within a changeset.  Please report this as a bug.  Changesetdata = "
Changeset: 40495
User: AAA\DavidC
Date: May 3, 2013 5:37:50 PM
Comment:
  Commit 853906c (Fri May 03 17:37:43 2013 +1000)
Author: David Clark <david.clark@hotelscombined.com>
Committer: David Clark <david.clark@hotelscombined.com>

".
null
FATAL: Aborted
Done. Took 4.1 sec
No changes

Here is a test that demonstrates the problem. Add this to DetailedHistoryCommandTest:

    @Bug(16208)
    @Test
    public void assertChangesetSeparatorAllowedWithinComment() throws Exception {
        StringBuilder builder = new StringBuilder("-------------------------------------------------------------------------------\n" +
                "Changeset: 123456\n" +
                "User: domain\\somebody\n" +
                "Date: Dec 26, 2012 3:00:15 PM\n" +
                "\n" +
                "Comment:\n" +
                "  Some comment goes here\n" +
                "------------------------------------------------------------------\n" +
                "  more of my comment\n" +
                "\n" +
                "\n" +
                "Items:\n" +
                "  edit $/somepath/to/file\n" +
                "\n" +
                "Check-in Notes:\n" +
                "  Dependencies: none\n" +
                "  Developer Notes: none \n"
        );

        StringReader stringReader = new StringReader(builder.toString());
        DetailedHistoryCommand command = new DetailedHistoryCommand(mock(ServerConfigurationProvider.class), "$/tfsandbox", Util.getCalendar(2008, 01, 15), Calendar.getInstance());
        List<ChangeSet> list = command.parse(stringReader);
        assertEquals("Number of change sets was incorrect", 1, list.size());
    }

Dig a little digging on this....looks like the problem is that our developer used "------------" within his changeset comment. This causes the code at line 247 of DetailedHistoryCommand (in the ChangeSetStringReader.readChangeSet method) to think that a new changeset is starting. We can fix the comment for now to avoid the problem. Is there any way to make the ChangeSetStringReader parser smarter somehow?