Using expressions in a mirrorOf element brakes the downloading of depencies

Since 2.0.9 Maven supports the usage of expressions in the 'mirrorOf' element
(See http://maven.apache.org/guides/mini/guide-mirror-settings.html)

These expression are not wel interpreted by the dependencies task.

The snippet
<dependencies pathId="xy1.path" settingsFile="${basedir}/settings.xml">
<dependency groupId="x" artifactId="y" version="1" type="pom"/>
</dependencies>
works when settings.xml is:
<settings>
...
<mirrors>
<mirror>
<mirrorOf>project-releases-repository</mirrorOf>
<url>http://the.maven.proxy/project...</url>
</mirror>
<mirror>
<mirrorOf>*</mirrorOf>
<url>http://the.maven.proxy/public...</url>
</mirror>
</mirrors>
...
</settings>

It stops working (= not able to download dependency) when settings.xml is:
<settings>
...
<mirrors>
<mirror>
<mirrorOf>*,!project-releases-repository</mirrorOf>
<url>http://the.maven.proxy/public...</url>
</mirror>
</mirrors>
...
</settings>