Sprouts looks interesting
Sprouts is an open-source, cross-platform project generation and configuration tool for ActionScript 2, ActionScript 3, Adobe AIR and Flex projects.
So it looks like it uses Ruby (and Gem) to set up a project like Rails and resolve dependencies a la Maven (but Ivy might be a better comparision), and provides some missing glue in the form of ant (rake?) tasks for continuous integration.
Here’s a link about the alternative using Maven.
A note about Sprouts and a Flex Maven plugin (see the comments):
— it sounds here that Sprouts is really geared towards a project jumpstarter. The comment by Luke Bayes talks about finding, download, and installing the Flex SDK, Flash Debug Player, a trace log reader, asunit or flexunit, and any other project dependency libraries. It then creates a project directory structure, and apparently has integration with CI tools, (especially) CruiseControl.rb.
Another post on Sprouts