mvn archetype:generate is failing to download needed archetype artifacts

A fresh install of Maven 2.0.9 on Windows XP, if I issue this command:

mvn archetype:generate -DarchetypeArtifactId=maven-archetype-quickstart

I get this error message:
[INFO] The desired archetype does not exist (org.apache.maven.archetypes:maven-archetype-quickstart:1.0)

Partial error stack:
[INFO] Scanning for projects...
[INFO] Searching repository for plugin with prefix: 'archetype'.
[INFO] ------------------------------------------------------------------------
[INFO] Building Maven Default Project
[INFO] task-segment: [archetype:generate] (aggregator-style)
[INFO] ------------------------------------------------------------------------
[INFO] Preparing archetype:generate
[INFO] No goals needed for project - skipping
[INFO] Setting property: classpath.resource.loader.class => 'org.codehaus.plexus
.velocity.ContextClassLoaderResourceLoader'.
[INFO] Setting property: velocimacro.messages.on => 'false'.
[INFO] Setting property: resource.loader => 'classpath'.
[INFO] Setting property: resource.manager.logwhenfound => 'false'.
[INFO] [archetype:generate]
org.apache.maven.archetype.downloader.DownloadNotFoundException: Requested downl
oad does not exist.
at org.apache.maven.archetype.downloader.DefaultDownloader.download(Defa
ultDownloader.java:62)
at org.apache.maven.archetype.common.DefaultArchetypeArtifactManager.exi
sts(DefaultArchetypeArtifactManager.java:310)
at org.apache.maven.archetype.ui.DefaultArchetypeGenerationConfigurator.
configureArchetype(DefaultArchetypeGenerationConfigurator.java:103)

The same error also happens with an archetype artifact ID of "maven-archetype-webapp" (and probably all the others as well).

However, if I issue the same command but using archetype:create instead of :generate, not only will the archetype artifact correctly download (and the command work successfully), subsequent usages of archetype:generate with that same archetype artifact will also correctly run.

So I think the problem is that mvn archetype:generate needs to download archetype artifacts just like mvn archetype:create does.