Gradle Integration and Custom Source Sets

I'm using IntelliJ 13 and have a Gradle project with some custom source set mappings:

sourceSets {    integrationTest {        compileClasspath = sourceSets.main.output + configurations.testRuntime        runtimeClasspath = output + sourceSets.main.output + configurations.testRuntime        groovy {            srcDir = 'src/testIntegration/groovy'        }        resources {            srcDir 'src/testIntegration/resources'        }    }} 
task testIntegration(type: Test) {    testClassesDir = sourceSets.integrationTest.output.classesDir    classpath = sourceSets.integrationTest.runtimeClasspath} 

Every time I click the refresh in the Gradle window, the folder src/testIntegration/groovy becomes unmarked as a 'Test Sources Root'.

How do I convince IntelliJ's Gradle integration that the src/testIntegration/groovy folder contains test source code?