diff --git a/libc/tools/zoneinfo/ZoneCompactor.java b/libc/tools/zoneinfo/ZoneCompactor.java
index 814ef5b98..9fb9ceca7 100644
--- a/libc/tools/zoneinfo/ZoneCompactor.java
+++ b/libc/tools/zoneinfo/ZoneCompactor.java
@@ -5,7 +5,7 @@ import java.util.*;
 import libcore.io.BufferIterator;
 import libcore.util.ZoneInfo;
 
-// usage: java ZoneCompiler <setup file> <top-level directory>
+// usage: java ZoneCompiler <setup file> <data directory> <output directory> <tzdata version>
 //
 // Compile a set of tzfile-formatted files into a single file plus
 // an index file.
@@ -121,12 +121,12 @@ public class ZoneCompactor {
         os.write( x        & 0xff);
     }
 
-    public ZoneCompactor(String setupFilename, String dirName) throws Exception {
-        File zoneInfoFile = new File("zoneinfo.dat");
+    public ZoneCompactor(String setupFile, String dataDirectory, String outputDirectory, String version) throws Exception {
+        File zoneInfoFile = new File(outputDirectory, "zoneinfo.dat");
         zoneInfoFile.delete();
         OutputStream zoneInfo = new FileOutputStream(zoneInfoFile);
 
-        BufferedReader rdr = new BufferedReader(new FileReader(setupFilename));
+        BufferedReader rdr = new BufferedReader(new FileReader(setupFile));
 
         String s;
         while ((s = rdr.readLine()) != null) {
@@ -140,7 +140,7 @@ public class ZoneCompactor {
             } else {
                 String link = links.get(s);
                 if (link == null) {
-                    File f = new File(dirName, s);
+                    File f = new File(dataDirectory, s);
                     long length = f.length();
                     starts.put(s, new Integer(start));
                     lengths.put(s, new Integer((int)length));
@@ -168,7 +168,7 @@ public class ZoneCompactor {
             offsets.put(from, offsets.get(to));
         }
 
-        File idxFile = new File("zoneinfo.idx");
+        File idxFile = new File(outputDirectory, "zoneinfo.idx");
         idxFile.delete();
         FileOutputStream idx = new FileOutputStream(idxFile);
 
@@ -194,14 +194,19 @@ public class ZoneCompactor {
         }
         idx.close();
 
+        OutputStreamWriter writer = new OutputStreamWriter(new FileOutputStream(new File(outputDirectory, "zoneinfo.version")), "US-ASCII");
+        writer.write(version);
+        writer.write('\n');
+        writer.close();
+
         // System.out.println("maxLength = " + maxLength);
     }
 
     public static void main(String[] args) throws Exception {
-        if (args.length != 2) {
-            System.err.println("usage: java ZoneCompactor <setup> <data dir>");
+        if (args.length != 4) {
+            System.err.println("usage: java ZoneCompactor <setup file> <data directory> <output directory> <tzdata version>");
             System.exit(0);
         }
-        new ZoneCompactor(args[0], args[1]);
+        new ZoneCompactor(args[0], args[1], args[2], args[3]);
     }
 }
diff --git a/libc/tools/zoneinfo/generate b/libc/tools/zoneinfo/generate
index fd4e6d09b..1dfbd8ed9 100755
--- a/libc/tools/zoneinfo/generate
+++ b/libc/tools/zoneinfo/generate
@@ -88,24 +88,13 @@ def upgrade_to(ftp, filename):
     setup.write('%s\n' % zone)
   setup.close()
 
-  print 'Calling ZoneCompactor...'
+  print 'Calling ZoneCompactor to update bionic from %s to %s...' % (current_tzdata_version(), version)
   libcore_src_dir = '%s/../libcore/luni/src/main/java/' % bionic_dir
   subprocess.check_call(['javac', '-d', '.',
                          '%s/ZoneCompactor.java' % bionic_libc_tools_zoneinfo_dir,
                          '%s/libcore/util/ZoneInfo.java' % libcore_src_dir,
                          '%s/libcore/io/BufferIterator.java' % libcore_src_dir])
-  subprocess.check_call(['java', 'ZoneCompactor', 'setup', 'data'])
-
-  print 'Updating bionic from %s to %s...' % (current_tzdata_version(), version)
-  # Move the .dat and .idx files...
-  os.remove('%s/zoneinfo.dat' % bionic_libc_zoneinfo_dir)
-  shutil.move('zoneinfo.dat', bionic_libc_zoneinfo_dir)
-  os.remove('%s/zoneinfo.idx' % bionic_libc_zoneinfo_dir)
-  shutil.move('zoneinfo.idx', bionic_libc_zoneinfo_dir)
-  # Write the .version file...
-  zoneinfo_version = open('%s/zoneinfo.version' % bionic_libc_zoneinfo_dir, 'wb+')
-  zoneinfo_version.write('%s\n' % version)
-  zoneinfo_version.close()
+  subprocess.check_call(['java', 'ZoneCompactor', 'setup', 'data', bionic_libc_zoneinfo_dir, version])
 
 
 # URL from "Sources for Time Zone and Daylight Saving Time Data"