diff --git a/pkgs/development/interpreters/tcl/generic.nix b/pkgs/development/interpreters/tcl/generic.nix
index 6ce6e35189bf..894ed91de5c9 100644
--- a/pkgs/development/interpreters/tcl/generic.nix
+++ b/pkgs/development/interpreters/tcl/generic.nix
@@ -1,4 +1,5 @@
 { lib, stdenv, callPackage, makeSetupHook
+, tzdata
 
 # Version specific stuff
 , release, version, src
@@ -15,6 +16,14 @@ let
 
       setOutputFlags = false;
 
+      postPatch = ''
+        substituteInPlace library/clock.tcl \
+          --replace "/usr/share/zoneinfo" "${tzdata}/share/zoneinfo" \
+          --replace "/usr/share/lib/zoneinfo" "" \
+          --replace "/usr/lib/zoneinfo" "" \
+          --replace "/usr/local/etc/zoneinfo" ""
+      '';
+
       preConfigure = ''
         cd unix
       '';