groovy.lang.MissingMethodException: No signature of method

Hi, I'm a newbie trying to evaluate SoapUI for my team. I get an exception when I'm trying to set PropertyValue.. Any idea why? Here is my code and exception...


def testSuiteProps = testRunner.testCase.testSuite.properties
log.info testSuiteProps
testRunner.testCase.testSuite.properties.setPropertyValue("OrgService", "Value");


groovy.lang.MissingMethodException: No signature of method: java.util.HashMap.setPropertyValue() is applicable for argument types: (java.lang.String, java.lang.String) values: [OrgService, Value]

Thanks so much for your help..
raags