Compilar Spark no eclypse

Bom,

Segui passo a passo do artigo Spark SVN + Eclipse 3.3 + Subversive Installation Guide .

Contudo estou com problemas no build.xml.

Meu ambiente é o eclipse Helios com jdk 1.7.

Ocorre as seguintes mensagens de warning:

Description
Resource
Path
Location
Type
(1ª) taskdef class com.install4j.Install4JTask cannot be found
build.xml
/Talk/build
line 587
Ant Buildfile Problem
(2ª) taskdef class com.izforge.izpack.ant.IzPackTask cannot be found
build.xml
/Talk/build
line 866
Ant Buildfile Problem
(3ª) taskdef class net.sf.launch4j.ant.Launch4jTask cannot be found
build.xml
/Talk/build
line 440
Ant Buildfile Problem
(4ª) taskdef class net.sf.launch4j.ant.Launch4jTask cannot be found
build.xml
/Talk/build
line 888
Ant Buildfile Problem

Segue as linhas de código com warning:

1ª linha

<taskdef name=“install4j”

classname=“com.install4j.Install4JTask”

classpath="${installer.install4j.home}/bin/ant.jar"/>

2ª linha

<taskdef name=“IzPack”

classpath="${installer.izpack.dir}/lib/standalone-compiler.jar"

classname=“com.izforge.izpack.ant.IzPackTask”/>

3ª linha

<taskdef name=“launch4j”

classname=“net.sf.launch4j.ant.Launch4jTask”

classpath="${launch4j.dir}/launch4j.jar:${launch4j.dir}/lib/xstream.jar" />

4ª linha

<taskdef name=“launch4j”

classname=“net.sf.launch4j.ant.Launch4jTask”

classpath="${launch4j.dir}/launch4j.jar:${launch4j.dir}/lib/xstream.jar" />

Não tenho muita afinidade com o build por ant, qualquer ajuda agradeço.