Adding Apache common dependency to Play Framework 2.0

i want to import org.apache.commons.io but i'm getting this error:

[info] Compiling 1 Java source to /home/ghost/Bureau/app/play-2.0.1/waf/target/scala-2.9.1/classes...
[error] /home/ghost/Bureau/app/play-2.0.1/waf/app/controllers/Application.java:9: error: package org.apache.commons.io does not exist
[error]     import org.apache.commons.io.*;
[error]     ^
[error] /home/ghost/Bureau/app/play-2.0.1/waf/app/controllers/Application.java:41: error: cannot find symbol
[error]                 FileUtils.copyFile(file, destinationFile);
[error]                 ^
[error]   symbol:   variable FileUtils
[error]   location: class Application
[error] 2 errors
[error] {file:/home/ghost/Bureau/app/play-2.0.1/waf/}waf/compile:compile: javac returned nonzero exit code
[error] application - 

Play can't find package org.apache.commons.io . How can i add apache io as a dependency ?