Error with CURL

Issue

• Since our recent patching cycle our Web team has seen the following errors: "NSS error -8102" when using 'curl'.

# /usr/bin/curl --proxy proxy.example.com:8080 --cacert ~/etc/CA/ca.pem -v https://api.twitter.com
* About to connect() to proxy proxy.example.com port 8080 (#0)
*   Trying 192.168.1.1... connected
* Connected to proxy.example.com (192.168.1.1) port 8080 (#0)
* Establish HTTP proxy tunnel to api.twitter.com:443
> CONNECT api.twitter.com:443 HTTP/1.1
> Host: api.twitter.com:443
> User-Agent: curl/7.19.7 (x86_64-redhat-linux-gnu) libcurl/7.19.7 NSS/3.16.2.3 Basic ECC zlib/1.2.3 libidn/1.18 libssh2/1.4.2
> Proxy-Connection: Keep-Alive
> 
< HTTP/1.1 200 Connection established
< 
* Proxy replied OK to CONNECT request
* Initializing NSS with certpath: sql:/etc/pki/nssdb
*   CAfile: /etc/ca/ca.pem
  CApath: none
* Bad certificate received. Subject = 'CN=api.twitter.com,OU=Twitter Security,O="Twitter, Inc.",L=San Francisco,ST=CA,C=US', Issuer = 'CN=Webwasher Content Security,O=BIS,L=Basel,C=CH'
* NSS error -8102
* Closing connection #0
* Peer certificate cannot be authenticated with known CA certificates
curl: (60) Peer certificate cannot be authenticated with known CA certificates
More details here: http://curl.haxx.se/docs/sslcerts.html

curl performs SSL certificate verification by default, using a "bundle"
of Certificate Authority (CA) public keys (CA certs). If the default
bundle file isn't adequate, you can specify an alternate file
using the --cacert option.
If this HTTPS server uses a certificate signed by a CA represented in
the bundle, the certificate verification probably failed due to a
problem with the certificate (it might be expired, or the name might
not match the domain name in the URL).
If you'd like to turn off curl's verification of the certificate, use
the -k (or --insecure) option.

• There is no problem using 'wget'.