接收错误:使用npm时“error: SSL错误:SELF_SIGNED_CERT_IN_CHAIN”

I am using npm v1.0.104/node 0.6.12 on ubuntu - I am receiving the error copied below while attempting to install any new modules via npm (I tested socket.io earlier using http, not https though & am wondering if that could have resulted in the issue with npm/unsigned certs). The error pops up once npm tries to resolve the 'I am using npm v1.0.104/node 0.6.12 on ubuntu -