iron-sessionstorage sub path cookie bug

main.rs

extern crate iron;
extern crate mount;
extern crate router;
extern crate iron_sessionstorage;

use iron::prelude::*;
use iron_sessionstorage::SessionRequestExt;
use iron_sessionstorage::SessionStorage;
use iron_sessionstorage::backends::SignedCookieBackend;

struct MySession {
    pub id: i32
}

impl iron_sessionstorage::Value for MySession {
    fn get_key() -> &'static str { "X-My-Session" }
    fn into_raw(self) -> String { format!("{}", self.id) }
    fn from_raw(s: String) -> Option<Self> {
        s.parse::<i32>().map(|id| MySession { id: id }).ok()
    }
}

fn main() {
    let mut mount = mount::Mount::new();
    let mut router = router::Router::new();
    router.get("/login", |req: &mut Request| {
        match try!(req.session().get::<MySession>()) {
            Some(_) => Ok(Response::with("you're already logged in")),
            None => {
                req.session().set(MySession { id: 1 }).unwrap();
                Ok(Response::with("now logged in"))
            }
        }
    }, "login");
    router.get("/logout", |req: &mut Request| {
        match try!(req.session().get::<MySession>()) {
            Some(_) => {
                req.session().clear().unwrap();
                Ok(Response::with("now logged out"))
            }
            None => {
                Ok(Response::with("not logged in"))
            }
        }
    }, "logout");
    mount.mount("/path", router);
    let mut chain = Chain::new(mount);
    let secret = "changeme".as_bytes().to_vec();
    chain.link_around(SessionStorage::new(SignedCookieBackend::new(secret)));
    iron::Iron::new(chain).http("localhost:8080").unwrap();
    // Try logging out twice -- you'll see the cookie hasn't been cleared!
}

workaround.rs

use iron::prelude::*;
use iron::middleware::AfterMiddleware;
use iron::headers::SetCookie;

pub struct DeleteCookieMiddleware;
impl AfterMiddleware for DeleteCookieMiddleware {
    fn after(&self, _: &mut Request, mut res: Response) -> IronResult<Response> {
        {
            let headers = &mut res.headers;
            if let Some(sc) = headers.get_mut::<SetCookie>() {
                let SetCookie(ref mut cookies) = *sc;
                for c in cookies {
                    if c.starts_with("X-My-Session=; Max-Age=0;") {
                        c.push_str(";Path=/");
                    }
                }
            }
        }
        Ok(res)
    }
}