我尝试使用以下方法安装node.js模块：

npm install express

但我得到这个错误：

npm http GET https://registry.npmjs.org/express
npm ERR! TypeError: Request path contains unescaped characters.
npm ERR!     at Agent.request (_http_agent.js:264:11)
npm ERR!     at TunnelingAgent.exports.request (http.js:52:22)
npm ERR!     at TunnelingAgent.createSocket (/usr/local/lib/node_modules/npm/node_modules/request/node_modules/tunnel-agent/index.js:117:25)
npm ERR!     at TunnelingAgent.createSecureSocket [as createSocket] (/usr/local/lib/node_modules/npm/node_modules/request/node_modules/tunnel-agent/index.js:184:41)
npm ERR!     at TunnelingAgent.addRequest (/usr/local/lib/node_modules/npm/node_modules/request/node_modules/tunnel-agent/index.js:80:8)
npm ERR!     at new ClientRequest (_http_client.js:112:16)
npm ERR!     at Agent.request (_http_agent.js:279:10)
npm ERR!     at Object.exports.request (https.js:130:22)
npm ERR!     at Request.start (/usr/local/lib/node_modules/npm/node_modules/request/index.js:594:30)
npm ERR!     at Request.end (/usr/local/lib/node_modules/npm/node_modules/request/index.js:1186:28)
npm ERR! If you need help, you may report this log at:
npm ERR!     <http://github.com/isaacs/npm/issues>
npm ERR! or email it to:
npm ERR!     <npm-@googlegroups.com>

npm ERR! System Linux 3.6.11-7.fc16.x86_64
npm ERR! command "/usr/local/bin/node" "/usr/local/bin/npm" "install" "express"
npm ERR! cwd /usr/local/src/node
npm ERR! node -v v0.11.5-pre
npm ERR! npm -v 1.3.5
npm ERR! 
npm ERR! Additional logging details can be found in:
npm ERR!     /usr/local/src/node/npm-debug.log
npm ERR! not ok code 0

可能正在发生这种情况，因为我使用代理服务器，但我通过这种方式设置了代理服务器，以允许从网络外部的ips下载

export https_proxy='http://172.21.0.12:3128'

我希望你能帮帮我