go packer

yum install -y go
export GOPATH=$HOME/go
export PATH=$PATH:$GOPATH/bin
mkdir $GOPATH 

su -c 'rpm -Uvh http://dl.fedoraproject.org/pub/epel/5/i386/epel-release-5-4.noarch.rpm'
yum install -y bzr
rpm -ivy mercurial-3.4.1-0.x86_64.rpm
rpm -i 'http://pkgs.repoforge.org/rpmforge-release/rpmforge-release-0.5.3-1.el6.rf.x86_64.rpm'
rpm -i 'http://pkgs.repoforge.org/rpmforge-release/rpmforge-release-0.5.3-1.el6.rf.x86_64.rpm'
rpm --import http://apt.sw.be/RPM-GPG-KEY.dag.txt
vim /etc/yum.repos.d/rpmforge.repo
 => extras is enabled!
yum update git

go get -u github.com/mitchellh/gox
cd $GOPATH
cd src
cd github.com/mitchellh/
git clone https://github.com/mitchellh/packer
git checkout v0.7.1
cd packer/
make updatedeps
make
make dev

got packer v0.7.1