Non-jar dependencies cannot be resolved

Since Grails 1.3.2 any Ivy dependencies with a packaging other than "jar" do not resolve correctly. For example the Jetty plugin depends on JSP 2.0 (http://mirrors.ibiblio.org/pub/mirrors/maven2/org/mortbay/jetty/jsp-2.0/6.1.11/jsp-2.0-6.1.11.pom) which has packaging "pom". When Grails attempts to resolve the dependency it tries to look for a jar file. Something must be defaulting the expected packaging rather than reading it from the downloaded pom file.