Even if the build has failed, the ivy plugin triggers new builds of downstream
projects.
I found no configuration option for triggering other builds (when current is
stable, unstable, failed).
I'm using Ivy plugin 0.3 (with ivy 2.0) and hudson 1.310.

From Console output of a build:
[...]
Email was triggered for: Failure
There are 1 triggered emails.
Sending email for trigger: Failure
Sending e-mails to: ...
No Subversion tagging for unsuccessful build.
Triggering a new build of ActionLib #58
Triggering a new build of Engine3D #44
Triggering a new build of InputLib #23
Finished: FAILURE
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