findbugs:gui after findbugs:check not working

in pom.xml:

<plugin>
<groupId>org.codehaus.mojo</groupId>
<artifactId>findbugs-maven-plugin</artifactId>
<version>2.3.3</version>
<configuration>
<xmlOutput>true</xmlOutput>
</configuration>
<dependencies>
<dependency>
<groupId>commons-collections</groupId>
<artifactId>commons-collections</artifactId>
<version>3.2.1</version>
</dependency>
</dependencies>
</plugin>

mvn clean compile findbugs:check
[INFO] Scanning for projects...
...
[INFO] >>> findbugs-maven-plugin:2.3.3:check (default-cli) @ example >>>
[INFO]
[INFO] — findbugs-maven-plugin:2.3.3:findbugs (findbugs) @ example —
[INFO] Fork Value is true
[java] Warnings generated: 2
[INFO] Done FindBugs Analysis....
[INFO]
[INFO] <<< findbugs-maven-plugin:2.3.3:check (default-cli) @ example <<<
[INFO]
[INFO] — findbugs-maven-plugin:2.3.3:check (default-cli) @ example —
[INFO] BugInstance size is 2
[INFO] Error size is 0
[INFO] ------------------------------------------------------------------------
[INFO] BUILD FAILURE
[INFO] ------------------------------------------------------------------------

mvn findbugs:gui
[INFO] Scanning for projects...
...
[INFO] — findbugs-maven-plugin:2.3.3:gui (default-cli) @ example —
[INFO] File Encoding is UTF-8
Exception in thread "main" java.util.zip.ZipException: Error opening C:\Users\Test\workspace\example\target\findbugsXml.xml
at edu.umd.cs.findbugs.classfile.impl.ZipFileCodeBase.<init>(ZipFileCodeBase.java:66)
at edu.umd.cs.findbugs.classfile.impl.ZipCodeBaseFactory.countUsingZipFile(ZipCodeBaseFactory.java:92)
at edu.umd.cs.findbugs.classfile.impl.ZipCodeBaseFactory.makeZipCodeBase(ZipCodeBaseFactory.java:46)
at edu.umd.cs.findbugs.classfile.impl.ClassFactory.createFilesystemCodeBase(ClassFactory.java:97)
at edu.umd.cs.findbugs.classfile.impl.FilesystemCodeBaseLocator.openCodeBase(FilesystemCodeBaseLocator.java:75)
at edu.umd.cs.findbugs.classfile.impl.ClassPathBuilder.processWorkList(ClassPathBuilder.java:564)
at edu.umd.cs.findbugs.classfile.impl.ClassPathBuilder.build(ClassPathBuilder.java:195)
at edu.umd.cs.findbugs.FindBugs2.buildClassPath(FindBugs2.java:584)
at edu.umd.cs.findbugs.FindBugs2.execute(FindBugs2.java:181)
at edu.umd.cs.findbugs.FindBugs.runMain(FindBugs.java:348)
at edu.umd.cs.findbugs.FindBugs2.main(FindBugs2.java:1057)
at edu.umd.cs.findbugs.LaunchAppropriateUI.launch(LaunchAppropriateUI.java:106)
at edu.umd.cs.findbugs.LaunchAppropriateUI.main(LaunchAppropriateUI.java:197)
[INFO] ------------------------------------------------------------------------
[INFO] BUILD FAILURE
[INFO] ------------------------------------------------------------------------

@@

The file C:\Users\Test\workspace\example\target\findbugsXml.xml exists and is a valid file.

Why doesn't running "findbugs:gui" right after "findbugs:check" work?