diff --git a/lib/ssl/ssl3con.c b/lib/ssl/ssl3con.c
index afab931..e5e620f 100644
--- a/lib/ssl/ssl3con.c
+++ b/lib/ssl/ssl3con.c
@@ -5436,7 +5436,7 @@ ssl3_SendClientHello(sslSocket *ss, PRBool resending)
      * the lock across the calls to ssl3_CallHelloExtensionSenders.
      */
     if (sid->u.ssl3.lock) {
-        PR_RWLock_Rlock(sid->u.ssl3.lock);
+        NSSRWLock_LockRead(sid->u.ssl3.lock);
     }
 
     if (isTLS || (ss->firstHsDone && ss->peerRequestedProtection)) {
@@ -5445,7 +5445,7 @@ ssl3_SendClientHello(sslSocket *ss, PRBool resending)
 
 	extLen = ssl3_CallHelloExtensionSenders(ss, PR_FALSE, maxBytes, NULL);
 	if (extLen < 0) {
-	    if (sid->u.ssl3.lock) { PR_RWLock_Unlock(sid->u.ssl3.lock); }
+	    if (sid->u.ssl3.lock) { NSSRWLock_UnlockRead(sid->u.ssl3.lock); }
 	    return SECFailure;
 	}
 	total_exten_len += extLen;
@@ -5472,7 +5472,7 @@ ssl3_SendClientHello(sslSocket *ss, PRBool resending)
     /* how many suites are permitted by policy and user preference? */
     num_suites = count_cipher_suites(ss, ss->ssl3.policy, PR_TRUE);
     if (!num_suites) {
-    	if (sid->u.ssl3.lock) { PR_RWLock_Unlock(sid->u.ssl3.lock); }
+    	if (sid->u.ssl3.lock) { NSSRWLock_UnlockRead(sid->u.ssl3.lock); }
     	return SECFailure;	/* count_cipher_suites has set error code. */
     }
 
@@ -5517,7 +5517,7 @@ ssl3_SendClientHello(sslSocket *ss, PRBool resending)
 
     rv = ssl3_AppendHandshakeHeader(ss, client_hello, length);
     if (rv != SECSuccess) {
-	if (sid->u.ssl3.lock) { PR_RWLock_Unlock(sid->u.ssl3.lock); }
+	if (sid->u.ssl3.lock) { NSSRWLock_UnlockRead(sid->u.ssl3.lock); }
 	return rv;	/* err set by ssl3_AppendHandshake* */
     }
 
@@ -5536,21 +5536,21 @@ ssl3_SendClientHello(sslSocket *ss, PRBool resending)
 	rv = ssl3_AppendHandshakeNumber(ss, ss->clientHelloVersion, 2);
     }
     if (rv != SECSuccess) {
-	if (sid->u.ssl3.lock) { PR_RWLock_Unlock(sid->u.ssl3.lock); }
+	if (sid->u.ssl3.lock) { NSSRWLock_UnlockRead(sid->u.ssl3.lock); }
 	return rv;	/* err set by ssl3_AppendHandshake* */
     }
 
     if (!resending) { /* Don't re-generate if we are in DTLS re-sending mode */
 	rv = ssl3_GetNewRandom(&ss->ssl3.hs.client_random);
 	if (rv != SECSuccess) {
-	    if (sid->u.ssl3.lock) { PR_RWLock_Unlock(sid->u.ssl3.lock); }
+	    if (sid->u.ssl3.lock) { NSSRWLock_UnlockRead(sid->u.ssl3.lock); }
 	    return rv;	/* err set by GetNewRandom. */
 	}
     }
     rv = ssl3_AppendHandshake(ss, &ss->ssl3.hs.client_random,
                               SSL3_RANDOM_LENGTH);
     if (rv != SECSuccess) {
-	if (sid->u.ssl3.lock) { PR_RWLock_Unlock(sid->u.ssl3.lock); }
+	if (sid->u.ssl3.lock) { NSSRWLock_UnlockRead(sid->u.ssl3.lock); }
 	return rv;	/* err set by ssl3_AppendHandshake* */
     }
 
@@ -5560,7 +5560,7 @@ ssl3_SendClientHello(sslSocket *ss, PRBool resending)
     else
 	rv = ssl3_AppendHandshakeNumber(ss, 0, 1);
     if (rv != SECSuccess) {
-	if (sid->u.ssl3.lock) { PR_RWLock_Unlock(sid->u.ssl3.lock); }
+	if (sid->u.ssl3.lock) { NSSRWLock_UnlockRead(sid->u.ssl3.lock); }
 	return rv;	/* err set by ssl3_AppendHandshake* */
     }
 
@@ -5568,14 +5568,14 @@ ssl3_SendClientHello(sslSocket *ss, PRBool resending)
 	rv = ssl3_AppendHandshakeVariable(
 	    ss, ss->ssl3.hs.cookie, ss->ssl3.hs.cookieLen, 1);
 	if (rv != SECSuccess) {
-	    if (sid->u.ssl3.lock) { PR_RWLock_Unlock(sid->u.ssl3.lock); }
+	    if (sid->u.ssl3.lock) { NSSRWLock_UnlockRead(sid->u.ssl3.lock); }
 	    return rv;	/* err set by ssl3_AppendHandshake* */
 	}
     }
 
     rv = ssl3_AppendHandshakeNumber(ss, num_suites*sizeof(ssl3CipherSuite), 2);
     if (rv != SECSuccess) {
-	if (sid->u.ssl3.lock) { PR_RWLock_Unlock(sid->u.ssl3.lock); }
+	if (sid->u.ssl3.lock) { NSSRWLock_UnlockRead(sid->u.ssl3.lock); }
 	return rv;	/* err set by ssl3_AppendHandshake* */
     }
 
@@ -5584,7 +5584,7 @@ ssl3_SendClientHello(sslSocket *ss, PRBool resending)
 	rv = ssl3_AppendHandshakeNumber(ss, TLS_EMPTY_RENEGOTIATION_INFO_SCSV,
 					sizeof(ssl3CipherSuite));
 	if (rv != SECSuccess) {
-	    if (sid->u.ssl3.lock) { PR_RWLock_Unlock(sid->u.ssl3.lock); }
+	    if (sid->u.ssl3.lock) { NSSRWLock_UnlockRead(sid->u.ssl3.lock); }
 	    return rv;	/* err set by ssl3_AppendHandshake* */
 	}
 	actual_count++;
@@ -5593,7 +5593,7 @@ ssl3_SendClientHello(sslSocket *ss, PRBool resending)
 	rv = ssl3_AppendHandshakeNumber(ss, TLS_FALLBACK_SCSV,
 					sizeof(ssl3CipherSuite));
 	if (rv != SECSuccess) {
-	    if (sid->u.ssl3.lock) { PR_RWLock_Unlock(sid->u.ssl3.lock); }
+	    if (sid->u.ssl3.lock) { NSSRWLock_UnlockRead(sid->u.ssl3.lock); }
 	    return rv;	/* err set by ssl3_AppendHandshake* */
 	}
 	actual_count++;
@@ -5603,7 +5603,7 @@ ssl3_SendClientHello(sslSocket *ss, PRBool resending)
 	if (config_match(suite, ss->ssl3.policy, PR_TRUE, &ss->vrange, ss)) {
 	    actual_count++;
 	    if (actual_count > num_suites) {
-		if (sid->u.ssl3.lock) { PR_RWLock_Unlock(sid->u.ssl3.lock); }
+		if (sid->u.ssl3.lock) { NSSRWLock_UnlockRead(sid->u.ssl3.lock); }
 		/* set error card removal/insertion error */
 		PORT_SetError(SSL_ERROR_TOKEN_INSERTION_REMOVAL);
 		return SECFailure;
@@ -5611,7 +5611,7 @@ ssl3_SendClientHello(sslSocket *ss, PRBool resending)
 	    rv = ssl3_AppendHandshakeNumber(ss, suite->cipher_suite,
 					    sizeof(ssl3CipherSuite));
 	    if (rv != SECSuccess) {
-		if (sid->u.ssl3.lock) { PR_RWLock_Unlock(sid->u.ssl3.lock); }
+		if (sid->u.ssl3.lock) { NSSRWLock_UnlockRead(sid->u.ssl3.lock); }
 		return rv;	/* err set by ssl3_AppendHandshake* */
 	    }
 	}
@@ -5622,14 +5622,14 @@ ssl3_SendClientHello(sslSocket *ss, PRBool resending)
      * the server.. */
     if (actual_count != num_suites) {
 	/* Card removal/insertion error */
-	if (sid->u.ssl3.lock) { PR_RWLock_Unlock(sid->u.ssl3.lock); }
+	if (sid->u.ssl3.lock) { NSSRWLock_UnlockRead(sid->u.ssl3.lock); }
 	PORT_SetError(SSL_ERROR_TOKEN_INSERTION_REMOVAL);
 	return SECFailure;
     }
 
     rv = ssl3_AppendHandshakeNumber(ss, numCompressionMethods, 1);
     if (rv != SECSuccess) {
-	if (sid->u.ssl3.lock) { PR_RWLock_Unlock(sid->u.ssl3.lock); }
+	if (sid->u.ssl3.lock) { NSSRWLock_UnlockRead(sid->u.ssl3.lock); }
 	return rv;	/* err set by ssl3_AppendHandshake* */
     }
     for (i = 0; i < compressionMethodsCount; i++) {
@@ -5637,7 +5637,7 @@ ssl3_SendClientHello(sslSocket *ss, PRBool resending)
 	    continue;
 	rv = ssl3_AppendHandshakeNumber(ss, compressions[i], 1);
 	if (rv != SECSuccess) {
-	    if (sid->u.ssl3.lock) { PR_RWLock_Unlock(sid->u.ssl3.lock); }
+	    if (sid->u.ssl3.lock) { NSSRWLock_UnlockRead(sid->u.ssl3.lock); }
 	    return rv;	/* err set by ssl3_AppendHandshake* */
 	}
     }
@@ -5648,20 +5648,20 @@ ssl3_SendClientHello(sslSocket *ss, PRBool resending)
 
 	rv = ssl3_AppendHandshakeNumber(ss, maxBytes, 2);
 	if (rv != SECSuccess) {
-	    if (sid->u.ssl3.lock) { PR_RWLock_Unlock(sid->u.ssl3.lock); }
+	    if (sid->u.ssl3.lock) { NSSRWLock_UnlockRead(sid->u.ssl3.lock); }
 	    return rv;	/* err set by AppendHandshake. */
 	}
 
 	extLen = ssl3_CallHelloExtensionSenders(ss, PR_TRUE, maxBytes, NULL);
 	if (extLen < 0) {
-	    if (sid->u.ssl3.lock) { PR_RWLock_Unlock(sid->u.ssl3.lock); }
+	    if (sid->u.ssl3.lock) { NSSRWLock_UnlockRead(sid->u.ssl3.lock); }
 	    return SECFailure;
 	}
 	maxBytes -= extLen;
 
 	extLen = ssl3_AppendPaddingExtension(ss, paddingExtensionLen, maxBytes);
 	if (extLen < 0) {
-	    if (sid->u.ssl3.lock) { PR_RWLock_Unlock(sid->u.ssl3.lock); }
+	    if (sid->u.ssl3.lock) { NSSRWLock_UnlockRead(sid->u.ssl3.lock); }
 	    return SECFailure;
 	}
 	maxBytes -= extLen;
@@ -5670,7 +5670,7 @@ ssl3_SendClientHello(sslSocket *ss, PRBool resending)
     } 
 
     if (sid->u.ssl3.lock) {
-        PR_RWLock_Unlock(sid->u.ssl3.lock);
+        NSSRWLock_UnlockRead(sid->u.ssl3.lock);
     }
 
     if (ss->xtnData.sentSessionTicketInClientHello) {
diff --git a/lib/ssl/sslimpl.h b/lib/ssl/sslimpl.h
index 3403091..874e59c 100644
--- a/lib/ssl/sslimpl.h
+++ b/lib/ssl/sslimpl.h
@@ -742,7 +742,7 @@ struct sslSessionIDStr {
 	     * cached. Before then, there is no need to lock anything because
 	     * the sid isn't being shared by anything.
 	     */
-	    PRRWLock *lock;
+	    NSSRWLock *lock;
 
 	    /* The lock must be held while reading or writing these members
 	     * because they change while the sid is cached.
diff --git a/lib/ssl/sslnonce.c b/lib/ssl/sslnonce.c
index cefdda6..28ad364 100644
--- a/lib/ssl/sslnonce.c
+++ b/lib/ssl/sslnonce.c
@@ -136,7 +136,7 @@ ssl_DestroySID(sslSessionID *sid)
         }
 
         if (sid->u.ssl3.lock) {
-            PR_DestroyRWLock(sid->u.ssl3.lock);
+            NSSRWLock_Destroy(sid->u.ssl3.lock);
         }
     }
 
@@ -308,7 +308,7 @@ CacheSID(sslSessionID *sid)
 	PRINT_BUF(8, (0, "sessionID:",
 		      sid->u.ssl3.sessionID, sid->u.ssl3.sessionIDLength));
 
-	sid->u.ssl3.lock = PR_NewRWLock(PR_RWLOCK_RANK_NONE, NULL);
+	sid->u.ssl3.lock = NSSRWLock_New(NSS_RWLOCK_RANK_NONE, NULL);
 	if (!sid->u.ssl3.lock) {
 	    return;
 	}
@@ -450,7 +450,7 @@ ssl3_SetSIDSessionTicket(sslSessionID *sid,
      * yet, so no locking is needed.
      */
     if (sid->u.ssl3.lock) {
-	PR_RWLock_Wlock(sid->u.ssl3.lock);
+	NSSRWLock_LockWrite(sid->u.ssl3.lock);
 	if (sid->u.ssl3.locked.sessionTicket.ticket.data) {
 	    SECITEM_FreeItem(&sid->u.ssl3.locked.sessionTicket.ticket,
 			     PR_FALSE);
@@ -465,6 +465,6 @@ ssl3_SetSIDSessionTicket(sslSessionID *sid,
     newSessionTicket->ticket.len = 0;
 
     if (sid->u.ssl3.lock) {
-	PR_RWLock_Unlock(sid->u.ssl3.lock);
+	NSSRWLock_UnlockWrite(sid->u.ssl3.lock);
     }
 }