Description:
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Making a request with curl and a client certificate won't work if the client certificate key is ciphered.

Curl will generate an error:
curl error (58): unable to load client key: -8178 (SEC_ERROR_BAD_KEY) 

It seems this is due to curl compiled with NSS because with curl compiled with openssl it works

If this is correct please could you update the documentation to warn about this?

Test script:
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curl_setopt($ch, CURLOPT_SSLCERT,       "<path to client PEM cert>");
curl_setopt($ch, CURLOPT_SSLKEY,        "<path to client PEM key>");
curl_setopt($ch, CURLOPT_SSLKEYPASSWD,  "password");




Expected result:
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The client certificate should be presented to remote

Actual result:
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If the private key begins with:
-----BEGIN PRIVATE KEY-----
--> it will work

If it begins with:
-----BEGIN ENCRYPTED PRIVATE KEY-----
--> it will generate "curl error (58): unable to load client key: -8178 (SEC_ERROR_BAD_KEY)"