karma-runner error: Cannot call method 'invoke' of undefined - karma-runner

Question

My karma runner is confusing me. Some tests run just fine but others, seemingly similar, don't.
This works:
it('should display an error when accessing /business-user without authentication', function() {
browser().navigateTo('../business-user');
expect(element('p#flash').text()).toBe('You must be logged in to access that page.');
});
This does not:
it('should take the user to the index lander upon logout', function() {
browser().navigateTo('../business-user/login');
input('username').enter('matt');
input('password').enter('letmein');
element('input:last').click();
element('a#logout').click();
expect(browser().window().path()).toBe('/');
});
Running the test as displayed gives me an error that a#logout cannot be found. I paused the runner to verify that a#logout was there, and it was. When I resume, I get the "TypeError: Cannot call method 'invoke' of undefined" error.
I would think the object that should be defined is the element, but why wouldn't it say that it can't find the element? And more importantly, why can't it find it in the first place?
Obligatory karma-e2e.conf.js dump:
// Karma configuration
// Generated on Tue Aug 20 2013 17:01:18 GMT-0600 (MDT)
module.exports = function(config) {
config.set({
basePath: '../..',
frameworks: ['ng-scenario'],
files: [
'test/e2e/*.js'
],
exclude: [
],
reporters: ['progress'],
port: 9876,
colors: true,
logLevel: config.LOG_INFO,
autoWatch: false,
browsers: ['Chrome'],
captureTimeout: 60000,
singleRun: true,
proxies: {
'/': 'http://localhost:3000/'
},
urlRoot: '/_karma_/'
});
};
Any ideas?