The bit of code that actually worked for me, as horrible as it looks is the standard document.location.href:
var sammy = Sammy(function () {
this.get('#/project/:projectId', function () {
// does some stuff with knockout.js
});
this.get('#/', function () {
// does some stuff with knockout.js
});
this.get('/logout', function () {
document.location.href = './logout';
});
this.get('', function () {
location.hash = '/';
});
});