andreas@nsn7:~$ openssl pkcs8 -topk8 -in cakey.pem -out cakey.p8
Enter pass phrase for cakey.pem:
Enter Encryption Password:
Verifying - Enter Encryption Password:
andreas@nsn7:~$ cat cakey.p8 
-----BEGIN ENCRYPTED PRIVATE KEY-----
MIIJaTAbBgkqhkiG9w0BBQMwDgQI4DK1r5h8neQCAggABIIJSDarhvVIT52didfq