the latest version is available for RED5 is 0.7 on site but download from google code using svn as the tarball of 0.7 on site is missing some of the files.
Export Variables for Ant & Java
export ANT_HOME=/usr/local/ant
export JAVA_HOME=/usr/lib/jvm/java
export PATH=$PATH:/usr/local/ant/bin
export CLASSPATH=.:$JAVA_HOME/lib/classes.zip