Can't install spock to grails 1.3.7 project
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I created a simple hello world grails app using Grails 1.3.7:

    grails create-app hello
    grails create-controller hello

Then I try to install the spock plugin using:

    grails install-plugin spock

And I get the following:

    Error loading event script from file [/Users/wholladay/.grails/1.3.7/projects/hello/plugins/spock-0.6/scripts/_Events.groovy] startup failed:
    Could not instantiate global transform class org.spockframework.compiler.SpockTransform specified at jar:file:/Users/wholladay/.ivy2/cache/org.spockframework/spock-core/jars/spock-core-0.6-groovy-1.8.jar!/META-INF/services/org.codehaus.groovy.transform.ASTTransformation  because of exception org.spockframework.util.IncompatibleGroovyVersionException: The Spock compiler plugin cannot execute because Spock 0.6.0-groovy-1.8 is not compatible with Groovy 1.7.8. For more information, see http://versioninfo.spockframework.org
    Spock location: file:/Users/wholladay/.ivy2/cache/org.spockframework/spock-core/jars/spock-core-0.6-groovy-1.8.jar
    Groovy location: file:/usr/local/Cellar/grails/current/lib/groovy-all-1.7.8.jar

So I went to: http://versioninfo.spockframework.org and noticed that there is a version 0.6-groovy-1.7 of spock. So I tried:

    grails install-plugin 0.6-groovy-1.7

But then I got the following error:

    Error resolving plugin [name:0.6-groovy-1.7, group:org.grails.plugins, version:latest.integration].
    Plugin not found for name [0.6-groovy-1.7] and version [not specified]

Any ideas?