Cannot build

[Ygarr]

Buildfile: //JWave/build.xml

clean:
[delete] Deleting directory //JWave/build

doMac:

doWin:

doUnix:
[echo] OS is a Unix target
[echo] JUnit path: /JWave/lib/junit4.jar

init:
[mkdir] Created dir: //JWave/build
[echo] OS Name is: Linux
[echo] OS Arch. is: amd64
[echo] OS Vers. is: 6.1.12-x64v1-xanmod1
[echo] JUnit path: //JWave/lib/junit4.jar
[echo] hamcrest path: //JWave/lib/hamcrest-all.jar

compile:
[javac] Compiling 104 source files to //JWave/build
[javac] error: error reading /JWave/lib/junit4.jar; zip END header not found

BUILD FAILED
//JWave/build.xml:99: Compile failed; see the compiler error output for details.

Total time: 0 seconds