 		 */
 		public function cacheInterstitial( location : String = null ) : void
 		{
-			if (location) extCtx.call('cacheInterstitial', location);
-			else extCtx.call('cacheInterstitial');
+			if (isChartboostSupported)
+			{
+				if (location) extCtx.call('cacheInterstitial', location);
+				else extCtx.call('cacheInterstitial');
+			}
 		}
 		
 		/**

				} 
				else
				{
					trace('[AirChartboost] Error - Extension Context is null.');
				}
				_instance = this;
			}

		 */
		public function startSession( appID : String, appSignature : String ) : void
		{
			if (isChartboostSupported)
				extCtx.call('startSession', appID, appSignature);
		}
		
		/**
