Cannot set gwt.version

[ghost]

When running grails app, I get the following:

Checking GWT home version[null] buildconfig[null] sysprop[null] antprop[null]
| Packaging Grails application
COMPILE START
| GWT does not appear to be configured, either set gwt.version in BuildConfig (preferred), or GWT must be installed and GWT_HOME environment must be set.

BuildConfig:
plugins {
build ":extended-dependency-manager:0.5.5"
compile ":gwt:1.0", {
transitive=false
}
}

gwt {
version = "2.5.1"
}

What am I doing wrong?

[oniseijin]

Try the 1.0.3 version, I have it working with version="2.6.1" and it downloads GWT just fine.