Wrong time stamps are generated by teamLastModified ant task

Hello there,
I'm running the following ant task to collect the last modified information from the plugin to update the timestamp of the plugin version.
<teamLastModified
repositoryAddress="${repositoryAddress}"
userId="${userId}"
passwordFile="${passwordFile}"
workspaceName="${workspaceName}"
outputPropertiesFile="${buildDirectory}/../jazzBuilds/logs/modified.properties"
sourceDirectory="${team.scm.fetchDestination}"
verbose="true" />
It works fine until I created a new stream to start a maintenance build. Here is the scenario.
1. Let's say the plugin was last changed on date A before the product was released
2. When the main stream came to release, a snapshot was taken. Let's say on date B.
3. The development keeps going on the main stream and new code gets into main stream.
4. When it's decided to ship a maintenance for the release, I need to get a stream from the release date B because the main stream contains the code which should not be included.
5. I create a new stream from the snapshot taken on date B and I was shocked to find that all the last updated time stamps were moved to date B. This means all the plugins would be reshipped in the fix pack.
6. I also tried to create a stream from snapshot of the build workspace. I got the same result

Is there something I can do to get the right date, which is date A?
Thanks.

Best Regards

Samuel Wu