Does Nexus correctly maintain maven-metadata.xml?

Hi,

I noticed that after a new snapshot has been deployed by Hudson, the
maven-metadata.xml file looks as follows:

<metadata>
  <groupId>org.apache.ws.commons.axiom</groupId>
  <artifactId>axiom-api</artifactId>
  <version>1.2.10-SNAPSHOT</version>
  <versioning>
    <snapshot>
      <buildNumber>1</buildNumber>
    </snapshot>
    <lastUpdated>20101015122432</lastUpdated>
  </versioning>
</metadata>

However, Nexus periodically regenerates the maven-metadata.xml file.
In the process, it removes the versioning information, as can be seen
in the following example:

<metadata>
  <groupId>org.apache.ws.commons.axiom</groupId>
  <artifactId>axiom-parser-tests</artifactId>
  <version>1.2.10-SNAPSHOT</version>
  <versioning />
</metadata>

Is that the correct behavior? I'm asking this because I have troubles
with some Hudson builds that are not fetching the latest snapshot from
Nexus, and I was wondering if this may be related.

Andreas