rc disabled is not triggering when there is change in value

[arjunasuresh3]

Angular js version - v1.2.7

var rcDisabledDirective = {
'rcDisabled': ['rcDisabled', function (rcDisabled) {
return {
restrict: 'A',
link: function (scope, element, attributes) {
scope.$watch(attributes.rcDisabled, function(isDisabled) {
rcDisabled.disable(element, isDisabled); // This is not getting triggered when there is change in submitInProgress value from false to true
});
}
}
}]
};