[Help]Build Failed

[vmlinuz]

Καμιά ιδέα κανείς

[mkdir] Created dir: C:\Users\admin\Desktop\l2j\l2j\build\classes

    [javac] C:\Users\admin\Desktop\l2j\l2j\build.xml:51: warning: 'includeantruntime' was not set, defaulting to build.sysclasspath=last; set to false for repeatable builds

    [javac] Compiling 100 source files to

C:\Users\admin\Desktop\l2j\l2j\build\classes

    [javac] warning: [options] bootstrap class path not set in conjunction with -source 1.5

    [javac] C:\Users\admin\Desktop\l2j\l2j\commons\src\main\java\catssoftware\L2Config.java:17: error: package org.apache.log4j does not exist

    [javac] import org.apache.log4j.Logger;

[mexis15]

Tell us what u do at java i thing u mistake in code.try explain more plz.