import scope dependencies prefer to download pom rather than find it in the current project

I've run into this in geronimo trunk.

Initial project state:

root pom includes dependency A in dependencyManagement.
this dependency is used (in dependencies) in several places including plugins/clustering/plugin-farm-datasource/

Snapshots for this project are deployed (at apache snapshot repo)

project update:
move A to dependencyManagement of plugins/system-database/pom.xml (also a pom packaging)
include in plugins/clustering/plugin-farm-datasource/pom.xml

<dependencyManagement>
<dependencies>
<dependency>
<groupId>org.apache.geronimo.plugins</groupId>
<artifactId>system-database</artifactId>
<version>${version}</version>
<type>pom</type>
<scope>import</scope>
</dependency>
</dependencies>
</dependencyManagement>

(this is a car packaging project, using the geronimo car-maven-plugin)

now, clean the local repo and try to build the project from root.

we see:

pb:trunk david$ mvn clean install -Pit
[INFO] Scanning for projects...
[INFO] snapshot org.apache.geronimo.plugins:system-database:2.2-SNAPSHOT: checking for updates from apache.snapshots
[INFO] snapshot org.apache.geronimo.plugins:system-database:2.2-SNAPSHOT: checking for updates from apache-snapshots
[INFO] snapshot org.apache.geronimo.plugins:system-database:2.2-SNAPSHOT: checking for updates from codehaus-snapshots
Downloading: http://people.apache.org/repo/m2-snapshot-repository/org/apache/geronimo/plugins/system-database/2.2-SNAPSHOT/system-database-2.2-SNAPSHOT.pom

rather than using the system-database pom in the local project it is downloading the obsolete snapshot.

I've worked around this by uploading the system-database pom by hand.

I may try to write a sample project but since seeing the bug depends on having a deployed snapshot and then changing it locally I have no idea how to write an automated test.