code: function RSAEncryptOAEP(text, hash, hashLen) {
    var m = oaep_pad(text, (this.n.bitLength() + 7) >> 3, hash, hashLen);
    if(m == null) return null;
    var c = this.doPublic(m);
    if(c == null) return null;
    var h = c.toString(16);
    if((h.length & 1) == 0) return h; else return "0" + h;
  }
docs: Return the PKCS#1 OAEP RSA encryption of "text" as an even-length hex string