diff -rN -u old-mbox/Data/MBox/String.hs new-mbox/Data/MBox/String.hs
--- old-mbox/Data/MBox/String.hs	2022-11-22 19:14:52.332543098 +0100
+++ new-mbox/Data/MBox/String.hs	2022-11-22 19:14:52.332543098 +0100
@@ -1,3 +1,4 @@
+{-# LANGUAGE CPP #-}
 
 -----------------------------------------------------------------------------
 {- |
@@ -31,7 +32,11 @@
 -- | Reads a date header as a UTCTime
 parseDateHeader :: String -> Maybe UTCTime
 parseDateHeader header = listToMaybe . catMaybes $ map tryParse formats where
+#if MIN_VERSION_time(1,9,0)
+  tryParse f = parseTimeM True LC.defaultTimeLocale f header
+#else
   tryParse f = parseTime LC.defaultTimeLocale f header
+#endif
   formats =
     [ "%a, %_d %b %Y %T %z"
     , "%a, %_d %b %Y %T %Z"
diff -rN -u old-mbox/Data/MBox.hs new-mbox/Data/MBox.hs
--- old-mbox/Data/MBox.hs	2022-11-22 19:14:52.332543098 +0100
+++ new-mbox/Data/MBox.hs	2022-11-22 19:14:52.332543098 +0100
@@ -1,3 +1,4 @@
+{-# LANGUAGE CPP #-}
 {-# LANGUAGE ViewPatterns #-}
 
 -----------------------------------------------------------------------------
@@ -34,7 +35,11 @@
 parseDateHeader :: T.Text -> Maybe UTCTime
 parseDateHeader txt = listToMaybe . catMaybes $ map tryParse formats where
   header = T.unpack txt
+#if MIN_VERSION_time(1,9,0)
+  tryParse f = parseTimeM True LC.defaultTimeLocale f header
+#else
   tryParse f = parseTime LC.defaultTimeLocale f header
+#endif
   formats =
     [ "%a, %_d %b %Y %T %z"
     , "%a, %_d %b %Y %T %Z"
diff -rN -u old-mbox/mbox.cabal new-mbox/mbox.cabal
--- old-mbox/mbox.cabal	2022-11-22 19:14:52.332543098 +0100
+++ new-mbox/mbox.cabal	2022-11-22 19:14:52.332543098 +0100
@@ -13,7 +13,7 @@
 Cabal-Version:       >= 1.6
 
 library
-  build-depends:     base >= 4, base < 6, safe, time < 1.9, time-locale-compat, text
+  build-depends:     base >= 4, base < 6, safe, time, time-locale-compat, text
   exposed-modules:   Data.MBox, Data.MBox.String
   ghc-options:       -Wall