在Ubuntu上不能使用PPA下载

sudo -i
export https_proxy='http://xxx.xxx.xxx.xxx:8080'
export http_proxy='http://xxx.xxx.xxx.xxx:8080'
sed -i 's/'keyserver.ubuntu.com'/'hkp:\/\/keyserver.ubuntu.com:80'/' /usr/share/pyshared/softwareproperties/ppa.py
LANG=C add-apt-repository ppa:nova-core/trunk

from:http://blog.sina.com.cn/u/1730614452