$ cat httpclient-test.rb
require 'rubygems'
require 'httpclient'
puts "httpclient version #{HTTPClient::VERSION}"
HTTPClient::SSLConfig.new nil
$ ruby httpclient-test.rb
httpclient version 2.1.5
cacerts: /Library/Ruby/Gems/1.8/gems/httpclient-2.1.5/lib/httpclient/cacert.p7s loading failed
I think I'm doing the openssl(1) equivalent command by extracting the embedded certificate in HTTPClient::SSL_Config and running openssl this way:
$ openssl verify -CAfile cafile -verbose /Library/Ruby/Gems/1.8/gems/httpclient-2.1.5/lib/httpclient/cacert.p7s
/Library/Ruby/Gems/1.8/gems/httpclient-2.1.5/lib/httpclient/cacert.p7s: /C=SE/O=AddTrust AB/OU=AddTrust TTP Network/CN=AddTrust Class 1 CA Root
error 18 at 0 depth lookup:self signed certificate
OK