[maven] How do you clear Apache Maven's cache?

Have you checked/changed the updatePolicy settings for your repositories in your settings.xml.

This element specifies how often updates should attempt to occur. Maven will compare the local POM's timestamp (stored in a repository's maven-metadata file) to the remote. The choices are: always, daily (default), interval:X (where X is an integer in minutes) or never.

Try to set it to always.