using option step in groovy syntax

hi,

I am playing around with webtest and first impressions are very good. but several pages are making problems with JS-errors so I want to set js-exception detection switched off (see http://webtest.canoo.com/webtest/manual/option.html).

I tried following but webtest gives me exception when while executing the option step, what is the correct way to use the option step in groovy:

class FirstWebTest extends WebtestCase {

  void testLogin() {
    //fails
    option name: "ThrowExceptionOnScriptError", value: "false"

    webtest("My first test") {
      group(description: "login to xxx") {
         //... test steps        
      }
    }
  }
}

thanks