Is there a way to use the RSA keys I've generated with the Crypto++ API in OpenSSL? What I am looking for is a way to store the keys in a format that both Crypto++ and OpenSSL can easily open them.

I'm writing a licensing scheme and would want to verify signatures and decrypt files using the Crypto++ API, but to generate the license files I would want to use a web interface (probably using PHP, which only supports OpenSSL) to generate and encrypt/sign the licenses. 

I would write both applications using Crypto++ and call it from the PHP, but since the private key will be stored in a encrypted form, a password must be passed to the application and passing it on the command line doesn't seems to be a good idea to me.