use bouncy castle to create public key on j2me

Question

I got the public key from the certificate, keypair is a java.security.KeyPair object

String public_key = keypair.getPublic().toString();

I want to send this to the via an http connection to a J2me application.

I cannot find any documentation to convert the transmitted string to a Public key that can be used to encrypt Strings.

I also want the J2me to verify signed strings from the server.

I want to then send the encrypted strings back to the server.