Exception in thread "main" java.lang.NoClassDefFoundError: org/apache/tools/ant/launch/Launcher

Alguem sabe como solucionar está exceção:
Exception in thread “main” java.lang.NoClassDefFoundError: org/apache/tools/ant/launch/Launcher

Algumas informações

Ambiente Linux Ubuntu 9

Variáveis de ambiente:
JAVA_HOME=/usr/lib/jvm/java-6-sun
CATALINA_HOME=/opt/apache-tomcat-6.0.24
ANT_HOME=/usr/share/ant
JRE_HOME=/usr/lib/jvm/java-6-sun/jre

------- Ant diagnostics report -------
Apache Ant version 1.7.1 compiled on November 10 2008


Implementation Version

core tasks : 1.7.1
optional tasks : not available


ANT PROPERTIES

ant.version: Apache Ant version 1.7.1 compiled on November 10 2008
ant.java.version: 1.6
ant.core.lib: /usr/share/ant/lib/ant.jar
ant.home: /usr/share/ant


ANT_HOME/lib jar listing

ant.home: /usr/share/ant
ant-commons-net.jar (47022 bytes)
ant-nodeps.jar (430942 bytes)
ant-trax.jar (6883 bytes)
ant-apache-log4j.jar (3061 bytes)
ant-apache-regexp.jar (3763 bytes)
ant-junit.jar (93510 bytes)
ant-jsch.jar (30793 bytes)
ant-apache-oro.jar (39624 bytes)
ant.jar (1345736 bytes)
ant-commons-logging.jar (3911 bytes)
ant-antlr.jar (5754 bytes)
ant-apache-resolver.jar (4071 bytes)
ant-launcher.jar (12146 bytes)
ant-swing.jar (6741 bytes)
ant-apache-bsf.jar (3941 bytes)
ant-javamail.jar (7000 bytes)
ant-apache-bcel.jar (8614 bytes)
ant-jmf.jar (6596 bytes)
ant-jdepend.jar (8138 bytes)


USER_HOME/.ant/lib jar listing

user.home: /root
No such directory.


Tasks availability

image : Not Available (the implementation class is not present)
sshexec : Missing dependency com.jcraft.jsch.UserInfo
wlrun : Not Available (the implementation class is not present)
scp : Missing dependency com.jcraft.jsch.UserInfo
stlist : Not Available (the implementation class is not present)
netrexxc : Not Available (the implementation class is not present)
starteam : Not Available (the implementation class is not present)
stylebook : Not Available (the implementation class is not present)
stlabel : Not Available (the implementation class is not present)
jdepend : Missing dependency jdepend.xmlui.JDepend
stcheckin : Not Available (the implementation class is not present)
stcheckout : Not Available (the implementation class is not present)
ejbc : Not Available (the implementation class is not present)
wlstop : Not Available (the implementation class is not present)
ddcreator : Not Available (the implementation class is not present)
A task being missing/unavailable should only matter if you are trying to use it


org.apache.env.Which diagnostics

Not available.
Download it at http://xml.apache.org/commons/


XML Parser information

XML Parser : org.apache.xerces.jaxp.SAXParserImpl
XML Parser Location: /usr/share/java/xercesImpl.jar
Namespace-aware parser : org.apache.xerces.jaxp.SAXParserImpl$JAXPSAXParser
Namespace-aware parser Location: /usr/share/java/xercesImpl.jar


System properties

java.runtime.name : Java™ SE Runtime Environment
sun.boot.library.path : /usr/lib/jvm/java-6-sun-1.6.0.16/jre/lib/i386
java.vm.version : 14.2-b01
ant.library.dir : /usr/share/ant/lib
java.vm.vendor : Sun Microsystems Inc.
java.vendor.url : http://java.sun.com/
path.separator : :
java.vm.name : Java HotSpot™ Server VM
file.encoding.pkg : sun.io
user.country : BR
sun.java.launcher : SUN_STANDARD
sun.os.patch.level : unknown
java.vm.specification.name : Java Virtual Machine Specification
user.dir : /home/danielr
java.runtime.version : 1.6.0_16-b01
java.awt.graphicsenv : sun.awt.X11GraphicsEnvironment
java.endorsed.dirs : /usr/lib/jvm/java-6-sun-1.6.0.16/jre/lib/endorsed
os.arch : i386
java.io.tmpdir : /tmp
line.separator :

java.vm.specification.vendor : Sun Microsystems Inc.
os.name : Linux
ant.home : /usr/share/ant
sun.jnu.encoding : UTF-8
java.library.path : /usr/lib/jvm/java-6-sun-1.6.0.16/jre/lib/i386/server:/usr/lib/jvm/java-6-sun-1.6.0.16/jre/lib/i386:/usr/lib/jvm/java-6-sun-1.6.0.16/jre/…/lib/i386:/usr/java/packages/lib/i386:/lib:/usr/lib
java.specification.name : Java Platform API Specification
java.class.version : 50.0
sun.management.compiler : HotSpot Tiered Compilers
os.version : 2.6.28-18-generic
user.home : /root
user.timezone : America/Bahia
java.awt.printerjob : sun.print.PSPrinterJob
file.encoding : UTF-8
java.specification.version : 1.6
user.name : root
java.class.path : /usr/share/ant/lib/ant-launcher.jar:/usr/share/java/xmlParserAPIs.jar:/usr/share/java/xercesImpl.jar:/opt/apache-tomcat-6.0.24/common/lib/jsp-api.jar:/opt/apache-tomcat-6.0.24/common/lib/servlet-api.jar:/usr/share/ant/lib/ant-commons-net.jar:/usr/share/ant/lib/ant-nodeps.jar:/usr/share/ant/lib/ant-trax.jar:/usr/share/ant/lib/ant-apache-log4j.jar:/usr/share/ant/lib/ant-apache-regexp.jar:/usr/share/ant/lib/ant-junit.jar:/usr/share/ant/lib/ant-jsch.jar:/usr/share/ant/lib/ant-apache-oro.jar:/usr/share/ant/lib/ant.jar:/usr/share/ant/lib/ant-commons-logging.jar:/usr/share/ant/lib/ant-antlr.jar:/usr/share/ant/lib/ant-apache-resolver.jar:/usr/share/ant/lib/ant-launcher.jar:/usr/share/ant/lib/ant-swing.jar:/usr/share/ant/lib/ant-apache-bsf.jar:/usr/share/ant/lib/ant-javamail.jar:/usr/share/ant/lib/ant-apache-bcel.jar:/usr/share/ant/lib/ant-jmf.jar:/usr/share/ant/lib/ant-jdepend.jar:/usr/lib/jvm/java-6-sun-1.6.0.16/lib/tools.jar
java.vm.specification.version : 1.0
sun.arch.data.model : 32
java.home : /usr/lib/jvm/java-6-sun-1.6.0.16/jre
java.specification.vendor : Sun Microsystems Inc.
user.language : pt
java.vm.info : mixed mode
java.version : 1.6.0_16
java.ext.dirs : /usr/lib/jvm/java-6-sun-1.6.0.16/jre/lib/ext:/usr/java/packages/lib/ext
sun.boot.class.path : /usr/lib/jvm/java-6-sun-1.6.0.16/jre/lib/resources.jar:/usr/lib/jvm/java-6-sun-1.6.0.16/jre/lib/rt.jar:/usr/lib/jvm/java-6-sun-1.6.0.16/jre/lib/sunrsasign.jar:/usr/lib/jvm/java-6-sun-1.6.0.16/jre/lib/jsse.jar:/usr/lib/jvm/java-6-sun-1.6.0.16/jre/lib/jce.jar:/usr/lib/jvm/java-6-sun-1.6.0.16/jre/lib/charsets.jar:/usr/lib/jvm/java-6-sun-1.6.0.16/jre/classes
java.vendor : Sun Microsystems Inc.
file.separator : /
java.vendor.url.bug : http://java.sun.com/cgi-bin/bugreport.cgi
sun.cpu.endian : little
sun.io.unicode.encoding : UnicodeLittle
sun.cpu.isalist :


Temp dir

Temp dir is /tmp
Temp dir is writeable
Temp dir alignment with system clock is -98 ms


Locale information

Timezone Brasilia Time offset=-10800000


Proxy information

Java1.5+ proxy settings:
Direct connection

ok… mas vc não disse oque vc estava fazendo ou que código executou que resultou neste erro.

Esta exception ocorre quando o java não encontra uma determinada classe no classpath da aplicação. Verifique se todas as dependências estão no classpath da sua aplicação.

Eu estava instalando um simulador chamado NEKO (sistemas distribuido)
http://ddsg.jaist.ac.jp/neko/index.html

O problema eh que eu executo um script ./configure que ja vem com a distribuição

Eu estou sem idéia de onde começar para corrigir este erro.