install_protobuf2.5.md

wget https://github.com/google/protobuf/releases/download/v2.5.0/protobuf-2.5.0.tar.gz
tar xvf protobuf-2.5.0.tar.gz
cd protobuf-2.5.0
./autogen.sh
./configure --prefix=/usr
make
sudo make install
protoc --version