diff --git a/coreapi/linphonecore_jni.cc b/coreapi/linphonecore_jni.cc
index fc6b76f1f..115f4a6fb 100644
--- a/coreapi/linphonecore_jni.cc
+++ b/coreapi/linphonecore_jni.cc
@@ -910,7 +910,7 @@ static jobject getOrCreateProxy(JNIEnv* env,LinphoneProxyConfig* proxy){
 extern "C" jobjectArray Java_org_linphone_core_LinphoneCoreImpl_getProxyConfigList(JNIEnv* env, jobject thiz, jlong lc) {
 	const MSList* proxies = linphone_core_get_proxy_config_list((LinphoneCore*)lc);
 	int proxyCount = ms_list_size(proxies);
-	jclass cls = env->FindClass("java/lang/Object");
+	jclass cls = env->FindClass("org/linphone/core/LinphoneProxyConfigImpl");
 	jobjectArray jProxies = env->NewObjectArray(proxyCount,cls,NULL);
 
 	for (int i = 0; i < proxyCount; i++ ) {
diff --git a/java/impl/org/linphone/core/LinphoneChatRoomImpl.java b/java/impl/org/linphone/core/LinphoneChatRoomImpl.java
index 8aa9c258d..b33f5db4b 100644
--- a/java/impl/org/linphone/core/LinphoneChatRoomImpl.java
+++ b/java/impl/org/linphone/core/LinphoneChatRoomImpl.java
@@ -44,37 +44,37 @@ class LinphoneChatRoomImpl implements LinphoneChatRoom {
 		nativePtr = aNativePtr;
 	}
 
-	public synchronized LinphoneAddress getPeerAddress() {
+	public LinphoneAddress getPeerAddress() {
 		return new LinphoneAddressImpl(getPeerAddress(nativePtr),LinphoneAddressImpl.WrapMode.FromConst);
 	}
 
-	public synchronized void sendMessage(String message) {
+	public void sendMessage(String message) {
 		synchronized(getCore()){
 			sendMessage(nativePtr,message);
 		}
 	}
 	
 	@Override
-	public synchronized void sendMessage(LinphoneChatMessage message, StateListener listener) {
+	public void sendMessage(LinphoneChatMessage message, StateListener listener) {
 		synchronized(getCore()){
 			sendMessage2(nativePtr, message, ((LinphoneChatMessageImpl)message).getNativePtr(), listener);
 		}
 	}
 
 	@Override
-	public synchronized LinphoneChatMessage createLinphoneChatMessage(String message) {
+	public LinphoneChatMessage createLinphoneChatMessage(String message) {
 		synchronized(getCore()){
 			return new LinphoneChatMessageImpl(createLinphoneChatMessage(nativePtr, message));
 		}
 	}
 	
-	public synchronized LinphoneChatMessage[] getHistory() {
+	public LinphoneChatMessage[] getHistory() {
 		synchronized(getCore()){
 			return getHistory(0);
 		}
 	}
 	
-	public synchronized LinphoneChatMessage[] getHistory(int limit) {
+	public LinphoneChatMessage[] getHistory(int limit) {
 		synchronized(getCore()){
 			long[] typesPtr = getHistory(nativePtr, limit);
 			if (typesPtr == null) return null;
@@ -88,48 +88,48 @@ class LinphoneChatRoomImpl implements LinphoneChatRoom {
 		}
 	}
 	
-	public synchronized void destroy() {
+	public void destroy() {
 		destroy(nativePtr);
 	}
 	
-	public synchronized int getUnreadMessagesCount() {
+	public int getUnreadMessagesCount() {
 		synchronized(getCore()){
 			return getUnreadMessagesCount(nativePtr);
 		}
 	}
 	
-	public synchronized void deleteHistory() {
+	public void deleteHistory() {
 		synchronized(getCore()){
 			deleteHistory(nativePtr);
 		}
 	}
 
-	public synchronized void compose() {
+	public void compose() {
 		synchronized(getCore()){
 			compose(nativePtr);
 		}
 	}
 
-	public synchronized boolean isRemoteComposing() {
+	public boolean isRemoteComposing() {
 		synchronized(getCore()){
 			return isRemoteComposing(nativePtr);
 		}
 	}
 	
-	public synchronized void markAsRead() {
+	public void markAsRead() {
 		synchronized(getCore()){
 			markAsRead(nativePtr);
 		}
 	}
 	
-	public synchronized void deleteMessage(LinphoneChatMessage message) {
+	public void deleteMessage(LinphoneChatMessage message) {
 		synchronized(getCore()){
 			if (message != null)
 				deleteMessage(nativePtr, ((LinphoneChatMessageImpl)message).getNativePtr());
 		}
 	}
 	
-	public synchronized void updateUrl(LinphoneChatMessage message) {
+	public void updateUrl(LinphoneChatMessage message) {
 		synchronized(getCore()){
 			if (message != null)
 				updateUrl(nativePtr, ((LinphoneChatMessageImpl)message).getNativePtr());
@@ -137,7 +137,7 @@ class LinphoneChatRoomImpl implements LinphoneChatRoom {
 	}
 	
 	@Override
-	public synchronized LinphoneChatMessage createLinphoneChatMessage(String message,
+	public LinphoneChatMessage createLinphoneChatMessage(String message,
 			String url, State state, long timestamp, boolean isRead,
 			boolean isIncoming) {
 		synchronized(getCore()){
diff --git a/java/impl/org/linphone/core/LinphoneEventImpl.java b/java/impl/org/linphone/core/LinphoneEventImpl.java
index ca9c2151c..c78b5da40 100644
--- a/java/impl/org/linphone/core/LinphoneEventImpl.java
+++ b/java/impl/org/linphone/core/LinphoneEventImpl.java
@@ -33,7 +33,7 @@ public class LinphoneEventImpl implements LinphoneEvent {
 
 	private native int notify(long nativeptr, String type, String subtype, byte data[], String encoding);
 	@Override
-	public synchronized void notify(LinphoneContent content) {
+	public void notify(LinphoneContent content) {
 		synchronized(getCore()){
 			notify(mNativePtr,content.getType(),content.getSubtype(),content.getData(),content.getEncoding());
 		}
@@ -41,7 +41,7 @@ public class LinphoneEventImpl implements LinphoneEvent {
 
 	private native int updateSubscribe(long nativePtr, String type, String subtype, byte data[], String encoding);
 	@Override
-	public synchronized void updateSubscribe(LinphoneContent content) {
+	public void updateSubscribe(LinphoneContent content) {
 		synchronized(getCore()){
 			updateSubscribe(mNativePtr,content.getType(), content.getSubtype(),content.getData(),content.getEncoding());
 		}
@@ -49,7 +49,7 @@ public class LinphoneEventImpl implements LinphoneEvent {
 
 	private native int updatePublish(long nativePtr, String type, String subtype, byte data[], String encoding);
 	@Override
-	public synchronized void updatePublish(LinphoneContent content) {
+	public void updatePublish(LinphoneContent content) {
 		synchronized(getCore()){
 			updatePublish(mNativePtr,content.getType(), content.getSubtype(),content.getData(),content.getEncoding());
 		}
@@ -57,7 +57,7 @@ public class LinphoneEventImpl implements LinphoneEvent {
 
 	private native int terminate(long nativePtr);
 	@Override
-	public synchronized void terminate() {
+	public void terminate() {
 		synchronized(getCore()){
 			terminate(mNativePtr);
 		}
@@ -115,7 +115,7 @@ public class LinphoneEventImpl implements LinphoneEvent {
 
 	private native void sendSubscribe(long ptr, String type, String subtype, byte data [], String encoding);
 	@Override
-	public synchronized void sendSubscribe(LinphoneContent body) {
+	public void sendSubscribe(LinphoneContent body) {
 		synchronized(getCore()){
 			if (body != null)
 				sendSubscribe(mNativePtr, body.getType(), body.getSubtype(), body.getData(), body.getEncoding());
@@ -126,7 +126,7 @@ public class LinphoneEventImpl implements LinphoneEvent {
 	
 	private native void sendPublish(long ptr, String type, String subtype, byte data [], String encoding);
 	@Override
-	public synchronized void sendPublish(LinphoneContent body) {
+	public void sendPublish(LinphoneContent body) {
 		synchronized(getCore()){
 			if (body != null)
 				sendPublish(mNativePtr, body.getType(), body.getSubtype(), body.getData(), body.getEncoding());