diff --git a/ssl/test/runner/cipher_suites.go b/ssl/test/runner/cipher_suites.go
index 89e75c8..62b8100 100644
--- a/ssl/test/runner/cipher_suites.go
+++ b/ssl/test/runner/cipher_suites.go
@@ -289,7 +289,7 @@
 }
 
 func rsaKA(version uint16) keyAgreement {
-	return &rsaKeyAgreement{}
+	return &rsaKeyAgreement{version: version}
 }
 
 func ecdheECDSAKA(version uint16) keyAgreement {
diff --git a/ssl/test/runner/common.go b/ssl/test/runner/common.go
index b505c8f..ff8c2d7 100644
--- a/ssl/test/runner/common.go
+++ b/ssl/test/runner/common.go
@@ -562,9 +562,10 @@
 	// retransmit at the record layer.
 	SequenceNumberIncrement uint64
 
-	// RSAServerKeyExchange, if true, causes the server to send a
-	// ServerKeyExchange message in the plain RSA key exchange.
-	RSAServerKeyExchange bool
+	// RSAEphemeralKey, if true, causes the server to send a
+	// ServerKeyExchange message containing an ephemeral key (as in
+	// RSA_EXPORT) in the plain RSA key exchange.
+	RSAEphemeralKey bool
 
 	// SRTPMasterKeyIdentifer, if not empty, is the SRTP MKI value that the
 	// client offers when negotiating SRTP. MKI support is still missing so
diff --git a/ssl/test/runner/key_agreement.go b/ssl/test/runner/key_agreement.go
index 116dfd8..efb032e 100644
--- a/ssl/test/runner/key_agreement.go
+++ b/ssl/test/runner/key_agreement.go
@@ -25,19 +25,73 @@
 // rsaKeyAgreement implements the standard TLS key agreement where the client
 // encrypts the pre-master secret to the server's public key.
 type rsaKeyAgreement struct {
+	version       uint16
 	clientVersion uint16
+	exportKey     *rsa.PrivateKey
 }
 
 func (ka *rsaKeyAgreement) generateServerKeyExchange(config *Config, cert *Certificate, clientHello *clientHelloMsg, hello *serverHelloMsg) (*serverKeyExchangeMsg, error) {
 	// Save the client version for comparison later.
 	ka.clientVersion = versionToWire(clientHello.vers, clientHello.isDTLS)
 
-	if config.Bugs.RSAServerKeyExchange {
-		// Send an empty ServerKeyExchange message.
-		return &serverKeyExchangeMsg{}, nil
+	if !config.Bugs.RSAEphemeralKey {
+		return nil, nil
 	}
 
-	return nil, nil
+	// Generate an ephemeral RSA key to use instead of the real
+	// one, as in RSA_EXPORT.
+	key, err := rsa.GenerateKey(config.rand(), 512)
+	if err != nil {
+		return nil, err
+	}
+	ka.exportKey = key
+
+	modulus := key.N.Bytes()
+	exponent := big.NewInt(int64(key.E)).Bytes()
+	serverRSAParams := make([]byte, 0, 2+len(modulus)+2+len(exponent))
+	serverRSAParams = append(serverRSAParams, byte(len(modulus)>>8), byte(len(modulus)))
+	serverRSAParams = append(serverRSAParams, modulus...)
+	serverRSAParams = append(serverRSAParams, byte(len(exponent)>>8), byte(len(exponent)))
+	serverRSAParams = append(serverRSAParams, exponent...)
+
+	var tls12HashId uint8
+	if ka.version >= VersionTLS12 {
+		if tls12HashId, err = pickTLS12HashForSignature(signatureRSA, clientHello.signatureAndHashes); err != nil {
+			return nil, err
+		}
+	}
+
+	digest, hashFunc, err := hashForServerKeyExchange(signatureRSA, tls12HashId, ka.version, clientHello.random, hello.random, serverRSAParams)
+	if err != nil {
+		return nil, err
+	}
+	privKey, ok := cert.PrivateKey.(*rsa.PrivateKey)
+	if !ok {
+		return nil, errors.New("RSA ephemeral key requires an RSA server private key")
+	}
+	sig, err := rsa.SignPKCS1v15(config.rand(), privKey, hashFunc, digest)
+	if err != nil {
+		return nil, errors.New("failed to sign RSA parameters: " + err.Error())
+	}
+
+	skx := new(serverKeyExchangeMsg)
+	sigAndHashLen := 0
+	if ka.version >= VersionTLS12 {
+		sigAndHashLen = 2
+	}
+	skx.key = make([]byte, len(serverRSAParams)+sigAndHashLen+2+len(sig))
+	copy(skx.key, serverRSAParams)
+	k := skx.key[len(serverRSAParams):]
+	if ka.version >= VersionTLS12 {
+		k[0] = tls12HashId
+		k[1] = signatureRSA
+		k = k[2:]
+	}
+	k[0] = byte(len(sig) >> 8)
+	k[1] = byte(len(sig))
+	copy(k[2:], sig)
+
+	return skx, nil
 }
 
 func (ka *rsaKeyAgreement) processClientKeyExchange(config *Config, cert *Certificate, ckx *clientKeyExchangeMsg, version uint16) ([]byte, error) {
@@ -60,7 +114,11 @@
 		ciphertext = ckx.ciphertext[2:]
 	}
 
-	err = rsa.DecryptPKCS1v15SessionKey(config.rand(), cert.PrivateKey.(*rsa.PrivateKey), ciphertext, preMasterSecret)
+	key := cert.PrivateKey.(*rsa.PrivateKey)
+	if ka.exportKey != nil {
+		key = ka.exportKey
+	}
+	err = rsa.DecryptPKCS1v15SessionKey(config.rand(), key, ciphertext, preMasterSecret)
 	if err != nil {
 		return nil, err
 	}
diff --git a/ssl/test/runner/runner.go b/ssl/test/runner/runner.go
index 6857358..69160b3 100644
--- a/ssl/test/runner/runner.go
+++ b/ssl/test/runner/runner.go
@@ -575,11 +575,11 @@
 		expectedError: ":WRONG_CIPHER_RETURNED:",
 	},
 	{
-		name: "RSAServerKeyExchange",
+		name: "RSAEphemeralKey",
 		config: Config{
 			CipherSuites: []uint16{TLS_RSA_WITH_AES_128_CBC_SHA},
 			Bugs: ProtocolBugs{
-				RSAServerKeyExchange: true,
+				RSAEphemeralKey: true,
 			},
 		},
 		shouldFail:    true,