Similar to bug 244688, we have reports of exceptions from task service invocation, the difference is that the cause is not an AuthenticationException but JsonParseException, which is due to an invalid response from the server (looks like html comes back instead of a json file). This seems to happen occasionally (no known steps to reproduce) and after the user has been successfully logged in.

org.codehaus.jackson.JsonParseException: Unexpected character ('<' (code 60)):
expected a valid value (number, String, array, object, 'true', 'false' or 'null')
 at [Source: java.io.InputStreamReader@66ecbbd0; line: 1, column: 2]
  org.codehaus.jackson.JsonParser._constructError(JsonParser.java:1432)
  org.codehaus.jackson.impl.JsonParserMinimalBase._reportError(JsonParserMinimalBase.java:385)
  org.codehaus.jackson.impl.JsonParserMinimalBase._reportUnexpectedChar(JsonParserMinimalBase.java:306)
  org.codehaus.jackson.impl.ReaderBasedParser._handleUnexpectedValue(ReaderBasedParser.java:1192)
  org.codehaus.jackson.impl.ReaderBasedParser.nextToken(ReaderBasedParser.java:479)
  org.codehaus.jackson.map.ObjectMapper._initForReading(ObjectMapper.java:2761)
  org.codehaus.jackson.map.ObjectMapper._readMapAndClose(ObjectMapper.java:2709)
  org.codehaus.jackson.map.ObjectMapper.readValue(ObjectMapper.java:1877)
  com.tasktop.c2c.server.common.service.web.ApacheResponseErrorHandler.handleError(ApacheResponseErrorHandler.java:111)
  com.tasktop.c2c.server.common.service.web.ApacheHttpRestClientDelegate.getForObject(ApacheHttpRestClientDelegate.java:379)
  com.tasktop.c2c.server.common.service.web.ApacheHttpRestClientDelegate.getForObject(ApacheHttpRestClientDelegate.java:217)
  com.tasktop.c2c.server.tasks.service.TaskServiceClient$GetCall.doCall(TaskServiceClient.java:286)
  com.tasktop.c2c.server.tasks.service.TaskServiceClient.getRepositoryContext(TaskServiceClient.java:422)
  o.eclipse.tools.cloud.dev.tasks.CloudDevClient.getRepositoryConfiguration(CloudDevClient.java:157)
  o.eclipse.tools.cloud.dev.tasks.CloudDevClient.getRepositoryConfiguration(CloudDevClient.java:140)
  org.netbeans.modules.odcs.tasks.repository.ODCSRepository.getRepositoryConfiguration(ODCSRepository.java:581) 
  org.netbeans.modules.odcs.tasks.repository.ODCSRepository.requestRemoteSavedQueries(ODCSRepository.java:414)
  org.netbeans.modules.odcs.tasks.repository.ODCSRepository.access$000(ODCSRepository.java:104)
  org.netbeans.modules.odcs.tasks.repository.ODCSRepository$1.run(ODCSRepository.java:401)
  org.openide.util.RequestProcessor$Task.run(RequestProcessor.java:1423)
  org.openide.util.RequestProcessor$Processor.run(RequestProcessor.java:2033)