diff --git a/Classes/LinphoneAppDelegate.h b/Classes/LinphoneAppDelegate.h
index 3428b1782..8b0076e3c 100644
--- a/Classes/LinphoneAppDelegate.h
+++ b/Classes/LinphoneAppDelegate.h
@@ -19,7 +19,7 @@
 
 #import <UIKit/UIKit.h>
 #import <AddressBookUI/ABPeoplePickerNavigationController.h>
-#import <CoreTelephony/CTCallCenter.h>
+
 
 #import "LinphoneCoreSettingsStore.h"
 
@@ -30,7 +30,6 @@
 @interface LinphoneAppDelegate : NSObject <UIApplicationDelegate,UIAlertViewDelegate> {
     @private
 	UIWindow *window;
-    CTCallCenter* callCenter;
     BOOL started;
 	int savedMaxCall;
 	
diff --git a/Classes/LinphoneAppDelegate.m b/Classes/LinphoneAppDelegate.m
index 3865666a1..259888f6a 100644
--- a/Classes/LinphoneAppDelegate.m
+++ b/Classes/LinphoneAppDelegate.m
@@ -56,17 +56,7 @@
 
 #pragma mark - 
 
-- (void)handleGSMCallInteration: (id) cCenter {
-    CTCallCenter* ct = (CTCallCenter*) cCenter;
-    
-    int callCount = [ct.currentCalls count];
-     /* pause current call, if any */
-     LinphoneCall* call = linphone_core_get_current_call([LinphoneManager getLc]);
-     if (callCount>0 && call) {
-          [LinphoneLogger logc:LinphoneLoggerLog format:"Pausing SIP call"];
-          linphone_core_pause_call([LinphoneManager getLc], call);
-      }
-}
+
 
 - (void)applicationDidEnterBackground:(UIApplication *)application{
 	[LinphoneLogger logc:LinphoneLoggerLog format:"applicationDidEnterBackground"];
@@ -94,13 +84,7 @@
 	}
     
     if (![[LinphoneManager instance] resignActive]) {
-        // destroying eventHandler if app cannot go in background.
-        // Otherwise if a GSM call happen and Linphone is resumed,
-        // the handler will be called before LinphoneCore is built.
-        // Then handler will be restored in appDidBecomeActive cb
-        callCenter.callEventHandler = nil;
-        [callCenter release];
-        callCenter = nil;
+
     }
     
 }
@@ -111,8 +95,6 @@
     
 	[[LinphoneManager instance] becomeActive];
     
-    // check call state at startup
-    [self handleGSMCallInteration:callCenter];
     
     LinphoneCore* lc = [LinphoneManager getLc];
     LinphoneCall* call = linphone_core_get_current_call(lc);
@@ -131,17 +113,7 @@
 	}
 }
 
-- (void)setupGSMInteraction {
-    if (callCenter == nil) {
-        callCenter = [[CTCallCenter alloc] init];
-        callCenter.callEventHandler = ^(CTCall* call) {
-            // post on main thread
-            [self performSelectorOnMainThread:@selector(handleGSMCallInteration:)
-                               withObject:callCenter
-                            waitUntilDone:YES];
-        };    
-    }
-}
+
 
 - (BOOL)application:(UIApplication *)application didFinishLaunchingWithOptions:(NSDictionary *)launchOptions {
     [[UIApplication sharedApplication] registerForRemoteNotificationTypes:UIRemoteNotificationTypeAlert|UIRemoteNotificationTypeSound|UIRemoteNotificationTypeBadge];
@@ -176,7 +148,7 @@
         [[LinphoneManager instance]	startLibLinphone];
     }
     if([LinphoneManager isLcReady]) {
-        [self setupGSMInteraction];
+        
         
         // Only execute one time at application start
         if(!started) {
diff --git a/Classes/LinphoneManager.h b/Classes/LinphoneManager.h
index 787828499..e96eb9bb2 100644
--- a/Classes/LinphoneManager.h
+++ b/Classes/LinphoneManager.h
@@ -22,6 +22,7 @@
 #import <SystemConfiguration/SCNetworkReachability.h>
 #import <AudioToolbox/AudioToolbox.h>
 #import <AssetsLibrary/ALAssetsLibrary.h>
+#import <CoreTelephony/CTCallCenter.h>
 
 #import <sqlite3.h>
 
@@ -88,6 +89,7 @@ typedef struct _LinphoneManagerSounds {
 	Connectivity connectivity;
     BOOL stopWaitingRegisters;
 	UIBackgroundTaskIdentifier pausedCallBgTask;
+	CTCallCenter* callCenter;
     
 @public
     CallContext currentCallContextBeforeGoingBackground;
diff --git a/Classes/LinphoneManager.m b/Classes/LinphoneManager.m
index a23bc620b..d6256750b 100644
--- a/Classes/LinphoneManager.m
+++ b/Classes/LinphoneManager.m
@@ -378,15 +378,11 @@ static void linphone_iphone_display_status(struct _LinphoneCore * lc, const char
 - (void)onCall:(LinphoneCall*)call StateChanged:(LinphoneCallState)state withMessage:(const char *)message {
     // Handling wrapper
     
-	CTCallCenter* ct = [[CTCallCenter alloc] init];
-    
-    int callCount = [ct.currentCalls count];
-    if (callCount>0 && state==LinphoneCallIncomingReceived) {
+    if ([callCenter currentCalls]!=nil && state==LinphoneCallIncomingReceived) {
 		[LinphoneLogger logc:LinphoneLoggerLog format:"Mobile call ongoing... rejecting call from [%s]",linphone_address_get_username(linphone_call_get_call_log(call)->from)];
 		linphone_core_terminate_call([LinphoneManager getLc], call);
 		return;
 	}
-	[ct release];
 	
 	if(state == LinphoneCallReleased) {
         LinphoneCallAppData* data = linphone_call_get_user_pointer(call);
@@ -657,8 +653,8 @@ static LinphoneCoreVTable linphonec_vtable = {
 #if HAVE_G729
 	libmsbcg729_init(); // load g729 plugin
 #endif
+	[self setupGSMInteraction];
 	/* Initialize linphone core*/
-	
     [LinphoneLogger logc:LinphoneLoggerLog format:"Create linphonecore"];
 	linphone_core_enable_logs_with_cb((OrtpLogFunc)linphone_iphone_log_handler);
 	theLinphoneCore = linphone_core_new (&linphonec_vtable
@@ -758,6 +754,14 @@ static LinphoneCoreVTable linphonec_vtable = {
 
 - (void)destroyLibLinphone {
 	[mIterateTimer invalidate]; 
+	// destroying eventHandler if app cannot go in background.
+	// Otherwise if a GSM call happen and Linphone is resumed,
+	// the handler will be called before LinphoneCore is built.
+	// Then handler will be restored in appDidBecomeActive cb
+	callCenter.callEventHandler = nil;
+	[callCenter release];
+	callCenter = nil;
+	
 	AVAudioSession *audioSession = [AVAudioSession sharedInstance];
 	[audioSession setDelegate:nil];
 
@@ -807,6 +811,7 @@ static int comp_call_id  (const LinphoneCall* call , const char *callid) {
 
 - (BOOL)resignActive {
 	linphone_core_stop_dtmf_stream(theLinphoneCore);
+
     return YES;
 }
 
@@ -985,8 +990,8 @@ static void audioRouteChangeListenerCallback (
 		return;
 	}
     
-    CTCallCenter* ct = [[CTCallCenter alloc] init];
-    if ([ct.currentCalls count] > 0) {
+    
+    if ([callCenter currentCalls]!=nil) {
         [LinphoneLogger logc:LinphoneLoggerError format:"GSM call in progress, cancelling outgoing SIP call request"];
 		UIAlertView* error = [[UIAlertView alloc]	initWithTitle:NSLocalizedString(@"Cannot make call",nil)
 														message:NSLocalizedString(@"Please terminate GSM call",nil) 
@@ -995,10 +1000,8 @@ static void audioRouteChangeListenerCallback (
 											  otherButtonTitles:nil];
 		[error show];
         [error release];
-        [ct release];
 		return;
     }
-    [ct release];
     
 	LinphoneProxyConfig* proxyCfg;	
 	//get default proxy
@@ -1194,4 +1197,27 @@ static void audioRouteChangeListenerCallback (
 	return [self lpConfigIntForKey:key forSection:section] == 1;
 }
 
+#pragma GSM management
+
+- (void)setupGSMInteraction {
+    if (callCenter == nil) {
+        callCenter = [[CTCallCenter alloc] init];
+        callCenter.callEventHandler = ^(CTCall* call) {
+            // post on main thread
+            [self performSelectorOnMainThread:@selector(handleGSMCallInteration:)
+								   withObject:callCenter
+								waitUntilDone:YES];
+        };
+    }
+}
+
+- (void)handleGSMCallInteration: (id) cCenter {
+    CTCallCenter* ct = (CTCallCenter*) cCenter;
+	/* pause current call, if any */
+	LinphoneCall* call = linphone_core_get_current_call(theLinphoneCore);
+	if ([ct currentCalls]!=nil && call) {
+		[LinphoneLogger logc:LinphoneLoggerLog format:"Pausing SIP call"];
+		linphone_core_pause_call(theLinphoneCore, call);
+	}
+}
 @end