在全新安装的 Ubuntu 上，使用 wget 时出现以下错误：
wget https://test.sagepay.com
--2012-03-27 12:55:12-- https://test.sagepay.com/
Resolving test.sagepay.com... 195.170.169.8
Connecting to test.sagepay.com|195.170.169.8|:443... connected.
ERROR: cannot verify test.sagepay.com's certificate, issued by `/C=US/O=VeriSign, Inc./OU=VeriSign Trust Network/OU=Terms of use at https://www.verisign.com/rpa (c)06/CN=VeriSign Class 3 Extended Validation SSL SGC CA':
Unable to locally verify the issuer's authority.
To connect to test.sagepay.com insecurely, use `--no-check-certificate'.
我试过安装 ca-certificates 并配置 ca-certs，它们似乎都设置在 /etc/ssl/certs.conf 中。
cURL 也存在同样的问题：
curl https://test.sagepay.com
curl: (60) SSL certificate problem, verify that the CA cert is OK. Details:
error:14090086:SSL routines:SSL3_GET_SERVER_CERTIFICATE:certificate verify …