diff --git a/CHANGELOG.md b/CHANGELOG.md
index 68c1b62..79d0670 100644
--- a/CHANGELOG.md
+++ b/CHANGELOG.md
@@ -8,6 +8,17 @@ Chrono obeys the principle of [Semantic Versioning](http://semver.org/).
 There were/are numerous minor versions before 1.0 due to the language changes.
 Versions with only mechnical changes will be omitted from the following list.
 
+## 0.2.3 (2015-02-27)
+
+### Added
+
+- `DateTime<Tz>` and `Date<Tz>` is now `Copy`/`Send` when `Tz::Offset` is `Copy`/`Send`.
+  The implementations for them were mistakenly omitted. (#25)
+
+### Fixed
+
+- `Local::from_utc_datetime` didn't set a correct offset. (#26)
+
 ## 0.2.1 (2015-02-21)
 
 ### Changed
diff --git a/Cargo.toml b/Cargo.toml
index 19d2226..525a32f 100644
--- a/Cargo.toml
+++ b/Cargo.toml
@@ -1,6 +1,6 @@
 [package]
 name = "chrono"
-version = "0.2.2"
+version = "0.2.3"
 authors = ["Kang Seonghoon <public+rust@mearie.org>"]
 
 description = "Date and time library for Rust"
diff --git a/README.md b/README.md
index 783fc69..a8331a7 100644
--- a/README.md
+++ b/README.md
@@ -1,4 +1,4 @@
-[Chrono][doc] 0.2.2
+[Chrono][doc] 0.2.3
 ===================
 
 [![Chrono on Travis CI][travis-image]][travis]
diff --git a/src/date.rs b/src/date.rs
index a726ead..4347d4c 100644
--- a/src/date.rs
+++ b/src/date.rs
@@ -284,6 +284,10 @@ impl<Tz: TimeZone> Datelike for Date<Tz> {
     }
 }
 
+// we need them as automatic impls cannot handle associated types
+impl<Tz: TimeZone> Copy for Date<Tz> where <Tz as TimeZone>::Offset: Copy {}
+unsafe impl<Tz: TimeZone> Send for Date<Tz> where <Tz as TimeZone>::Offset: Send {}
+
 impl<Tz: TimeZone, Tz2: TimeZone> PartialEq<Date<Tz2>> for Date<Tz> {
     fn eq(&self, other: &Date<Tz2>) -> bool { self.date == other.date }
 }
diff --git a/src/datetime.rs b/src/datetime.rs
index de6d4bb..12c0687 100644
--- a/src/datetime.rs
+++ b/src/datetime.rs
@@ -259,6 +259,10 @@ impl<Tz: TimeZone> Timelike for DateTime<Tz> {
     }
 }
 
+// we need them as automatic impls cannot handle associated types
+impl<Tz: TimeZone> Copy for DateTime<Tz> where <Tz as TimeZone>::Offset: Copy {}
+unsafe impl<Tz: TimeZone> Send for DateTime<Tz> where <Tz as TimeZone>::Offset: Send {}
+
 impl<Tz: TimeZone, Tz2: TimeZone> PartialEq<DateTime<Tz2>> for DateTime<Tz> {
     fn eq(&self, other: &DateTime<Tz2>) -> bool { self.datetime == other.datetime }
 }
@@ -403,6 +407,14 @@ mod tests {
                    NaiveTime::from_hms(7, 8, 9));
     }
 
+    #[test]
+    fn test_datetime_with_timezone() {
+        let local_now = Local::now();
+        let utc_now = local_now.with_timezone(&UTC);
+        let local_now2 = utc_now.with_timezone(&Local);
+        assert_eq!(local_now, local_now2);
+    }
+
     #[test]
     #[allow(non_snake_case)]
     fn test_datetime_rfc2822_and_rfc3339() {
@@ -466,5 +478,25 @@ mod tests {
         let dt = Local::now().with_month(5).unwrap();
         assert_eq!(dt.format("%Y").to_string(), dt.with_timezone(&UTC).format("%Y").to_string());
     }
+
+    #[test]
+    #[ignore] // XXX Rust issue #22818
+    fn test_datetime_is_copy() {
+        // UTC is known to be `Copy`.
+        let a = UTC::now();
+        let b = a;
+        assert_eq!(a, b);
+    }
+
+    #[test]
+    fn test_datetime_is_send() {
+        use std::thread;
+
+        // UTC is known to be `Send`.
+        let a = UTC::now();
+        thread::scoped(move || {
+            let _ = a;
+        }).join();
+    }
 }
 
diff --git a/src/lib.rs b/src/lib.rs
index 806ddca..600f020 100644
--- a/src/lib.rs
+++ b/src/lib.rs
@@ -4,7 +4,7 @@
 
 /*!
 
-# Chrono 0.2.2
+# Chrono 0.2.3
 
 Date and time handling for Rust. (also known as `rust-chrono`)
 It aims to be a feature-complete superset of the [time](https://github.com/rust-lang/time) library.
diff --git a/src/offset/local.rs b/src/offset/local.rs
index a4ca05d..6cf1ec3 100644
--- a/src/offset/local.rs
+++ b/src/offset/local.rs
@@ -35,7 +35,12 @@ fn tm_to_datetime(mut tm: stdtime::Tm) -> DateTime<Local> {
 }
 
 /// Converts a local `NaiveDateTime` to the `time::Timespec`.
-fn datetime_to_timespec(d: &NaiveDateTime) -> stdtime::Timespec {
+fn datetime_to_timespec(d: &NaiveDateTime, local: bool) -> stdtime::Timespec {
+    // well, this exploits an undocumented `Tm::to_timespec` behavior
+    // to get the exact function we want (either `timegm` or `mktime`).
+    // the number 1 is arbitrary but should be non-zero to trigger `mktime`.
+    let tm_utcoff = if local {1} else {0};
+
     let tm = stdtime::Tm {
         tm_sec: d.second() as i32,
         tm_min: d.minute() as i32,
@@ -46,8 +51,7 @@ fn datetime_to_timespec(d: &NaiveDateTime) -> stdtime::Timespec {
         tm_wday: 0, // to_local ignores this
         tm_yday: 0, // and this
         tm_isdst: -1,
-        tm_utcoff: 1, // this is arbitrary but should be nonzero
-                      // in order to make `to_timespec` use `rust_mktime` internally.
+        tm_utcoff: tm_utcoff,
         tm_nsec: d.nanosecond() as i32,
     };
     tm.to_timespec()
@@ -94,7 +98,7 @@ impl TimeZone for Local {
         self.from_local_datetime(&local.and_hms(0, 0, 0)).map(|datetime| datetime.date())
     }
     fn from_local_datetime(&self, local: &NaiveDateTime) -> LocalResult<DateTime<Local>> {
-        let timespec = datetime_to_timespec(local);
+        let timespec = datetime_to_timespec(local, true);
         LocalResult::Single(tm_to_datetime(stdtime::at(timespec)))
     }
 
@@ -102,8 +106,8 @@ impl TimeZone for Local {
         self.from_utc_datetime(&utc.and_hms(0, 0, 0)).date()
     }
     fn from_utc_datetime(&self, utc: &NaiveDateTime) -> DateTime<Local> {
-        let timespec = datetime_to_timespec(utc);
-        tm_to_datetime(stdtime::at_utc(timespec))
+        let timespec = datetime_to_timespec(utc, false);
+        tm_to_datetime(stdtime::at(timespec))
     }
 }