I get this "old daata" warning after update.
Can't finy any word about this in the changelogs.
Is this ok to be removed?

The error's stacktrace for a Free-Style Project:

Apr 07, 2014 8:02:38 AM hudson.util.RobustReflectionConverter doUnmarshal
WARNING: Skipping a non-existent field targetType
com.thoughtworks.xstream.converters.reflection.MissingFieldException: No field 'targetType' found in class 'hudson.plugins.jobConfigHistory.JobConfigBadgeAction'
at com.thoughtworks.xstream.converters.reflection.FieldDictionary.field(FieldDictionary.java:94)
at com.thoughtworks.xstream.converters.reflection.PureJavaReflectionProvider.getFieldType(PureJavaReflectionProvider.java:157)
at hudson.util.RobustReflectionConverter.determineType(RobustReflectionConverter.java:399)
at hudson.util.RobustReflectionConverter.doUnmarshal(RobustReflectionConverter.java:271)
at hudson.util.RobustReflectionConverter.unmarshal(RobustReflectionConverter.java:222)
at com.thoughtworks.xstream.core.TreeUnmarshaller.convert(TreeUnmarshaller.java:72)
at com.thoughtworks.xstream.core.AbstractReferenceUnmarshaller.convert(AbstractReferenceUnmarshaller.java:65)
at com.thoughtworks.xstream.core.TreeUnmarshaller.convertAnother(TreeUnmarshaller.java:66)
at com.thoughtworks.xstream.core.TreeUnmarshaller.convertAnother(TreeUnmarshaller.java:50)
at com.thoughtworks.xstream.converters.collections.AbstractCollectionConverter.readItem(AbstractCollectionConverter.java:71)
at hudson.util.RobustCollectionConverter.populateCollection(RobustCollectionConverter.java:85)
at com.thoughtworks.xstream.converters.collections.CollectionConverter.unmarshal(CollectionConverter.java:61)
at hudson.util.RobustCollectionConverter.unmarshal(RobustCollectionConverter.java:76)
at com.thoughtworks.xstream.core.TreeUnmarshaller.convert(TreeUnmarshaller.java:72)
at com.thoughtworks.xstream.core.AbstractReferenceUnmarshaller.convert(AbstractReferenceUnmarshaller.java:65)
at com.thoughtworks.xstream.core.TreeUnmarshaller.convertAnother(TreeUnmarshaller.java:66)
at hudson.util.RobustReflectionConverter.unmarshalField(RobustReflectionConverter.java:333)
at hudson.util.RobustReflectionConverter.doUnmarshal(RobustReflectionConverter.java:275)
at hudson.util.RobustReflectionConverter.unmarshal(RobustReflectionConverter.java:222)
at com.thoughtworks.xstream.core.TreeUnmarshaller.convert(TreeUnmarshaller.java:72)
at com.thoughtworks.xstream.core.AbstractReferenceUnmarshaller.convert(AbstractReferenceUnmarshaller.java:65)
at com.thoughtworks.xstream.core.TreeUnmarshaller.convertAnother(TreeUnmarshaller.java:66)
at com.thoughtworks.xstream.core.TreeUnmarshaller.convertAnother(TreeUnmarshaller.java:50)
at com.thoughtworks.xstream.core.TreeUnmarshaller.start(TreeUnmarshaller.java:134)
at com.thoughtworks.xstream.core.AbstractTreeMarshallingStrategy.unmarshal(AbstractTreeMarshallingStrategy.java:32)
at com.thoughtworks.xstream.XStream.unmarshal(XStream.java:1061)
at hudson.util.XStream2.unmarshal(XStream2.java:109)
at com.thoughtworks.xstream.XStream.unmarshal(XStream.java:1045)
at hudson.XmlFile.unmarshal(XmlFile.java:166)
at hudson.model.Run.reload(Run.java:310)
at hudson.model.Run.<init>(Run.java:299)
at hudson.model.AbstractBuild.<init>(AbstractBuild.java:180)
at hudson.model.Build.<init>(Build.java:103)
at hudson.model.FreeStyleBuild.<init>(FreeStyleBuild.java:41)
at sun.reflect.GeneratedConstructorAccessor105.newInstance(Unknown Source)
at sun.reflect.DelegatingConstructorAccessorImpl.newInstance(DelegatingConstructorAccessorImpl.java:45)
at java.lang.reflect.Constructor.newInstance(Constructor.java:526)
at hudson.model.AbstractProject.loadBuild(AbstractProject.java:1129)
at hudson.model.AbstractProject$1.create(AbstractProject.java:325)
at hudson.model.AbstractProject$1.create(AbstractProject.java:323)
at hudson.model.RunMap.retrieve(RunMap.java:225)
at hudson.model.RunMap.retrieve(RunMap.java:59)
at jenkins.model.lazy.AbstractLazyLoadRunMap.load(AbstractLazyLoadRunMap.java:674)
at jenkins.model.lazy.AbstractLazyLoadRunMap.load(AbstractLazyLoadRunMap.java:657)
at jenkins.model.lazy.AbstractLazyLoadRunMap.search(AbstractLazyLoadRunMap.java:499)
at jenkins.model.lazy.AbstractLazyLoadRunMap.getByNumber(AbstractLazyLoadRunMap.java:533)
at jenkins.model.lazy.AbstractLazyLoadRunMap.search(AbstractLazyLoadRunMap.java:379)
at jenkins.model.lazy.AbstractLazyLoadRunMap.newestBuild(AbstractLazyLoadRunMap.java:321)
at hudson.model.AbstractProject.getLastBuild(AbstractProject.java:1066)
at hudson.model.AbstractProject.getLastBuild(AbstractProject.java:144)
at hudson.plugins.disk_usage.DiskUsageThread.calculateWorkspaceDiskUsage(DiskUsageThread.java:124)
at hudson.plugins.disk_usage.DiskUsageThread.execute(DiskUsageThread.java:64)
at hudson.model.AsyncPeriodicWork$1.run(AsyncPeriodicWork.java:53)
at java.lang.Thread.run(Thread.java:724)

The sample JobConfigBadgeAction from build.xml:

<hudson.plugins.jobConfigHistory.JobConfigBadgeAction plugin="jobConfigHistory@2.4">
<targetType>hudson.model.AbstractBuild</targetType>
<configDates>
<string>2013-09-18_13-06-58</string>
<string>2013-05-27_06-38-21</string>
</configDates>
<build class="build" reference="../../.."/>
</hudson.plugins.jobConfigHistory.JobConfigBadgeAction>