diff --git a/README b/README
--- a/README
+++ b/README
@@ -79,25 +79,25 @@
 
 > take 10 $ recur monthly `starting` sep1997 $
 >   enumWeekDaysInMonth [Friday] >=>
->   nthWeekDayInMonth [1]
+>   nthWeekDayOfMonth [1]
 
 Monthly on the first Friday until Dec. 24, 1997
 
 > takeWhile (<= dec1997) $ recur monthly `starting` sep1997 $
 >   enumWeekDaysInMonth [Friday] >=>
->   nthWeekDayInMonth [1]
+>   nthWeekDayOfMonth [1]
 
 Every other month on the first and last Sunday of the month for 10 occurrences:
 
 > take 10 $ recur monthly `by` 2 `starting` sep1997 $
 >   enumWeekDaysInMonth [Sunday] >=>
->   nthWeekDayInMonth [1,-1]
+>   nthWeekDayOfMonth [1,-1]
 
 Monthly on the second-to-last Monday of the month for 6 months:
 
 > take 6 $ recur monthly `starting` sep1997 $
 >   enumWeekDaysInMonth [Monday] >=>
->   nthWeekDayInMonth [-2]
+>   nthWeekDayOfMonth [-2]
 
 Monthly on the third-to-last day of the month, forever:
 
@@ -186,7 +186,7 @@
 
 > take 3 $ recur monthly `starting` sep1997 $
 >   enumWeekDaysInMonth [Tuesday .. Thursday] >=>
->   nthWeekDayInMonth [3]
+>   nthWeekDayOfMonth [3]
 
 The second-to-last weekday of the month:
 
diff --git a/src/Data/Time/CalendarTime/CalendarTime.hs b/src/Data/Time/CalendarTime/CalendarTime.hs
--- a/src/Data/Time/CalendarTime/CalendarTime.hs
+++ b/src/Data/Time/CalendarTime/CalendarTime.hs
@@ -39,11 +39,13 @@
 class CalendarTimeConvertible t where
   -- | Convert to a 'CalendarTime'
   toCalendarTime :: t -> CalendarTime
+  toCalendarTimeWithTimeZone :: t -> TimeZone -> CalendarTime
   -- | Convert from a 'CalendarTime'
   fromCalendarTime :: CalendarTime -> Maybe t
 
 instance CalendarTimeConvertible CalendarTime where
   toCalendarTime = id
+  toCalendarTimeWithTimeZone ct tz = ct { calendarTimeZone = tz }
   fromCalendarTime = Just . id
 
 -- | Convert to a 'Day'
@@ -84,16 +86,20 @@
       (TimeOfDay hh mm ss) = timeToTimeOfDay utcTime
       (y, m, d, weekDay, yearDay) = dayInfo utcDay
 
+  toCalendarTimeWithTimeZone utcTime tz | tz == utc = toCalendarTime utcTime
+                                        | otherwise = error ("UTCTime.toCalendarTimeWithTimeZone cannot be represented with time zone " ++ show tz)
+
   fromCalendarTime t = do
     day <- toDay t
     time <- toTimeOfDay t
     return $ UTCTime day (timeOfDayToTime time)
 
 instance CalendarTimeConvertible LocalTime where
-  toCalendarTime (LocalTime day t) = CalendarTime (fromEnum $ todSec t) (todMin t) (todHour t) d (toEnum m) y weekDay yearDay tz
+  toCalendarTime _ = error ("LocalTime.toCalendarTime cannot be represented without a time zone")
+
+  toCalendarTimeWithTimeZone (LocalTime day t) tz = CalendarTime (fromEnum $ todSec t) (todMin t) (todHour t) d (toEnum m) y weekDay yearDay tz
     where
       (y, m, d, weekDay, yearDay) = dayInfo day
-      tz = unsafePerformIO getCurrentTimeZone
 
   fromCalendarTime t = do
     day <- toDay t
@@ -104,6 +110,8 @@
   toCalendarTime (ZonedTime (LocalTime day t) tz) = CalendarTime (fromEnum $ todSec t) (todMin t) (todHour t) d (toEnum m) y weekDay yearDay tz
     where
       (y, m, d, weekDay, yearDay) = dayInfo day
+
+  toCalendarTimeWithTimeZone (ZonedTime lt _) tz = toCalendarTime (ZonedTime lt tz)
 
   fromCalendarTime t = do
     day <- toDay t
diff --git a/time-recurrence.cabal b/time-recurrence.cabal
--- a/time-recurrence.cabal
+++ b/time-recurrence.cabal
@@ -7,7 +7,7 @@
 -- The package version. See the Haskell package versioning policy
 -- (http://www.haskell.org/haskellwiki/Package_versioning_policy) for
 -- standards guiding when and how versions should be incremented.
-Version:             0.5.2
+Version:             0.6
 
 -- A short (one-line) description of the package.
 Synopsis:            Generate recurring dates.
@@ -81,7 +81,7 @@
   
   -- Packages needed in order to build this package.
   Build-depends:       base >= 4 && < 5,
-                       time >= 1.2 && < 1.2.0.6,
+                       time >= 1.4.0.1 && < 1.5,
                        data-ordlist >= 0.4 && < 0.4.5,
                        mtl >= 2.0.1.0 && < 2.1
   
@@ -98,7 +98,7 @@
   main-is:              Tests.lhs
   ghc-options:          -Wall -fno-warn-name-shadowing
   build-depends:        base >= 4 && < 5,
-                        time >= 1.2 && < 1.2.0.6,
+                        time >= 1.4.0.1 && < 1.5,
                         data-ordlist >= 0.4 && < 0.4.5,
                         mtl >= 2.0.1.0 && < 2.1,
                         test-framework >= 0.4.0 && < 0.5,