diff --git a/NEWS b/NEWS
index 5d0d946..f6fa9a0 100644
--- a/NEWS
+++ b/NEWS
@@ -1,3 +1,10 @@
+= Version 0.4.0 =
+
+ZipFile is now mutable and provides a more convenient way of modifying
+zip archives than ZipOutputStream.
+
+Runs without warnings with -w switch.
+
 = Version 0.3.1 =
 
 Rudimentary support for writing zip archives.
diff --git a/TODO b/TODO
index 0400849..db482dc 100644
--- a/TODO
+++ b/TODO
@@ -3,9 +3,24 @@ write ZipFile.
 unit test writeFile (onExistsProc)
 unit test rename onExistsProc
 unit test yield on ZipFile::getInputStream
+unit test adding directories (and implement)
+unit test adding directories recursively (and implement)
+unit test ZipFile.checkIntegrity method (and implement)
+unit test and implement recursive extract (and implement)
+
+performance improve method
+ZipStreamableZipEntry.writeToZipOutputStream by not
+decompressing/compressing the data.
 
 release 0.4.0
 
+implement small gui app on top, to exercise library and to discover
+what features should be added to rubyzip. Use tk.
+
+implement setting the date correctly in ZipEntry with now as default
+
+release 0.4.1 with small gui demo app and fixes
+
 Refactor ZipFileTest to reduce duplicated code, divide into different
 test classes if different fixtures are required and use setup/teardown
 some more.
diff --git a/zip.rb b/zip.rb
index 9ff09c8..a253cc7 100755
--- a/zip.rb
+++ b/zip.rb
@@ -33,7 +33,7 @@ module Zip
     end
     
     def gets(aSepString=$/)
-      @outputBuffer="" unless @outputBuffer
+      @outputBuffer ||= ""
       return read if aSepString == nil
       aSepString="#{$/}#{$/}" if aSepString == ""
       
@@ -50,6 +50,7 @@ module Zip
     end
     
     def flush
+      @outputBuffer ||= ""
       retVal=@outputBuffer
       @outputBuffer=""
       return retVal
@@ -117,6 +118,7 @@ module Zip
       @archiveIO = File.open(filename, "rb")
       @archiveIO.seek(offset, IO::SEEK_SET)
       @decompressor = NullDecompressor.instance
+      @currentEntry = nil
     end
     
     def close
@@ -177,6 +179,7 @@ module Zip
       super
       @zlibInflater = Zlib::Inflate.new(-Zlib::Inflate::MAX_WBITS)
       @outputBuffer=""
+      @hasReturnedEmptyString = false
     end
     
     def read(numberOfBytes = nil)
@@ -265,6 +268,7 @@ module Zip
     
     def initialize(name = "", comment = "", extra = "", compressedSize = 0,   
 		   crc = 0, compressionMethod = ZipEntry::DEFLATED, size = 0)
+      @localHeaderOffset = 0
       @comment, @compressedSize, @crc, @extra, @compressionMethod, 
 	@name, @size, @isDirectory = comment, compressedSize, crc, 
 	extra, compressionMethod, name, size
@@ -352,11 +356,11 @@ module Zip
       
       io << 
 	[LOCAL_ENTRY_SIGNATURE    ,
-	@version                  ,
-	@gpFlags                  ,
+	0                         , # @version                  ,
+	0                         , # @gpFlags                  ,
 	@compressionMethod        ,
-	@lastModTime              ,
-	@lastModDate              ,
+	0                         , # @lastModTime              ,
+	0                         , # @lastModDate              ,
 	@crc                      ,
 	@compressedSize           ,
 	@size                     ,
@@ -420,12 +424,12 @@ module Zip
     def writeCDirEntry(io)
       io << 
 	[CENTRAL_DIRECTORY_ENTRY_SIGNATURE,
-	@version                          ,
-	@versionNeededToExtract           ,
-	@gpFlags                          ,
+	0                                 , # @version                          ,
+	0                                 , # @versionNeededToExtract           ,
+	0                                 , # @gpFlags                          ,
 	@compressionMethod                ,
-	@lastModTime                      ,
-	@lastModDate                      ,
+	0                                 , # @lastModTime                      ,
+	0                                 , # @lastModDate                      ,
 	@crc                              ,
 	@compressedSize                   ,
 	@size                             ,
@@ -433,8 +437,8 @@ module Zip
 	@extra ? @extra.length : 0        ,
 	@comment ? comment.length : 0     ,
 	0                                 , # disk number start
-	@internalFileAttributes           ,
-	@externalFileAttributes           ,
+	0                                 , # @internalFileAttributes           ,
+	0                                 , # @externalFileAttributes           ,
 	@localHeaderOffset                ,
 	@name                             ,
 	@extra                            ,
@@ -483,6 +487,9 @@ module Zip
       @outputStream = File.new(@fileName, "wb")
       @entries = []
       @compressor = NullCompressor.instance
+      @closed = false
+      @currentEntry = nil
+      @comment = nil
     end
 
     def ZipOutputStream.open(fileName)
@@ -707,7 +714,7 @@ module Zip
     end
     
     def each(&proc)
-      @entries.each &proc
+      @entries.each(&proc)
     end
 
     def ZipCentralDirectory.readFromStream(io)
@@ -734,6 +741,7 @@ module Zip
     
     def initialize(name)
       @name=name
+      @comment = ""
       File.open(name) {
 	|file|
 	readFromStream(file)
@@ -742,7 +750,7 @@ module Zip
     
     def BasicZipFile.foreach(aZipFileName, &block)
       zipFile = BasicZipFile.new(aZipFileName)
-      zipFile.each &block
+      zipFile.each(&block)
     end
     
     def getInputStream(entry)
@@ -772,6 +780,7 @@ module Zip
 
     def initialize(fileName, create = nil)
       @name = fileName
+      @comment = ""
       if (File.exists?(fileName))
 	super(fileName)
 	fixEntries
@@ -825,7 +834,7 @@ module Zip
     end
     
     def getInputStream(entry, &aProc)
-      getEntry(entry).getInputStream &aProc
+      getEntry(entry).getInputStream(&aProc)
     end
     
     def extract(entry, destPath, onExistsProc = proc { false })
diff --git a/ziptest.rb b/ziptest.rb
index efdb983..ef9dbfe 100755
--- a/ziptest.rb
+++ b/ziptest.rb
@@ -6,7 +6,6 @@ require 'zip'
 
 include Zip
 
-
 class AbstractInputStreamTest < RUNIT::TestCase
   # AbstractInputStream subclass that provides a read method
   
@@ -141,7 +140,7 @@ module IOizeString
   attr_reader :tell
   
   def read(count = nil)
-    @tell = 0 unless @tell
+    @tell ||= 0
     count = size unless count
     retVal = slice(@tell, count)
     @tell += count
@@ -149,6 +148,7 @@ module IOizeString
   end
 
   def seek(index, offset)
+    @tell ||= 0
     case offset
     when IO::SEEK_END
       newPos = size + index
@@ -165,6 +165,10 @@ module IOizeString
       @tell=newPos
     end
   end
+
+  def reset
+    @tell = 0
+  end
 end
 
 class ZipLocalEntryTest < RUNIT::TestCase
@@ -197,7 +201,7 @@ class ZipLocalEntryTest < RUNIT::TestCase
   def test_readLocalEntryFromTruncatedZipFile
     zipFragment=""
     File.open(TestZipFile::TEST_ZIP2.zipName) { |f| zipFragment = f.read(12) } # local header is at least 30 bytes
-    zipFragment.extend(IOizeString)
+    zipFragment.extend(IOizeString).reset
     entry = ZipEntry.new
     entry.readLocalEntry(zipFragment)
     fail "ZipError expected"
@@ -751,7 +755,7 @@ class ZipOutputStreamTest < RUNIT::TestCase
     begin
       zos = ZipOutputStream.open(name)
     rescue Exception
-      assert ($!.kind_of?(Errno::EISDIR) || $!.kind_of?(Errno::EEXIST),
+      assert($!.kind_of?(Errno::EISDIR) || $!.kind_of?(Errno::EEXIST),
 	      "Expected Errno::EISDIR (or on win/cygwin: Errno::EEXIST), but was: #{$!}")
     end
   end
@@ -781,7 +785,7 @@ module Enumerable
     index=0
     each_with_index {
       |element, index|
-      return false unless yield (element, otherAsArray[index])
+      return false unless yield(element, otherAsArray[index])
     }
     return index+1 == otherAsArray.size
   end
@@ -1051,14 +1055,14 @@ class ZipFileTest < RUNIT::TestCase
     File.copy(TestZipFile::TEST_ZIP2.zipName, TEST_ZIP.zipName)
 
     zf = ZipFile.new(TEST_ZIP.zipName)
-    assert(zf.entries.map { |e| e.name }.include? (entryToRemove))
+    assert(zf.entries.map { |e| e.name }.include?(entryToRemove))
     zf.remove(entryToRemove)
-    assert(! zf.entries.map { |e| e.name }.include? (entryToRemove))
+    assert(! zf.entries.map { |e| e.name }.include?(entryToRemove))
     assert_equals(zf.entries.map {|x| x.name }.sort, remainingEntries.sort) 
     zf.close
 
     zfRead = ZipFile.new(TEST_ZIP.zipName)
-    assert(! zfRead.entries.map { |e| e.name }.include? (entryToRemove))
+    assert(! zfRead.entries.map { |e| e.name }.include?(entryToRemove))
     assert_equals(zfRead.entries.map {|x| x.name }.sort, remainingEntries.sort) 
     zfRead.close
   end
@@ -1080,12 +1084,12 @@ class ZipFileTest < RUNIT::TestCase
 
   def test_extractNonEntry
     zf = ZipFile.new(TEST_ZIP.zipName)
-    assert_exception(ZipError) { zf.extract("nonExistingEntry") }
+    assert_exception(ZipError) { zf.extract("nonExistingEntry", "nonExistingEntry") }
   ensure
     zf.close if zf
   end
 
-  def test_extractNonEntry
+  def test_extractNonEntry2
     outFile = "outfile"
     assert_exception(ZipError) {
       zf = ZipFile.new(TEST_ZIP.zipName)
@@ -1286,7 +1290,6 @@ end
 TestZipFile::createTestZips(ARGV.index("recreate") != nil)
 TestFiles::createTestFiles(ARGV.index("recreate") != nil)
 
-
 # Copyright (C) 2002 Thomas Sondergaard
 # rubyzip is free software; you can redistribute it and/or
 # modify it under the terms of the ruby license.