json error

08-13 23:39:18.017: E/Servicio Rest(6395): Error!
08-13 23:39:18.017: E/Servicio Rest(6395): org.json.JSONException: Value {"tema":[{"idTema":"1","dsTema":"Todo lo referente a la historia de México","nbTema":"Historia de México"},{"idTema":"2","dsTema":"todo los relacionado con la cultura popular","nbTema":"Cultura Popular"},{"idTema":"3","dsTema":"todo lo relacionado con la historia","nbTema":"Historia"}]} of type org.json.JSONObject cannot be converted to JSONArray
08-13 23:39:18.017: E/Servicio Rest(6395): 	at org.json.JSON.typeMismatch(JSON.java:107)
08-13 23:39:18.017: E/Servicio Rest(6395): 	at org.json.JSONArray.<init>(JSONArray.java:91)
08-13 23:39:18.017: E/Servicio Rest(6395): 	at org.json.JSONArray.<init>(JSONArray.java:103)
08-13 23:39:18.017: E/Servicio Rest(6395): 	at com.mx.ipn.escom.clientRest.client.TemaClient.getTemas(TemaClient.java:34)
08-13 23:39:18.017: E/Servicio Rest(6395): 	at com.mx.ipn.escom.clientRest.activity.ClientRestActivity$1.onClick(ClientRestActivity.java:34)
08-13 23:39:18.017: E/Servicio Rest(6395): 	at android.view.View.performClick(View.java:2501)
08-13 23:39:18.017: E/Servicio Rest(6395): 	at android.view.View$PerformClick.run(View.java:9107)
08-13 23:39:18.017: E/Servicio Rest(6395): 	at android.os.Handler.handleCallback(Handler.java:587)
08-13 23:39:18.017: E/Servicio Rest(6395): 	at android.os.Handler.dispatchMessage(Handler.java:92)
08-13 23:39:18.017: E/Servicio Rest(6395): 	at android.os.Looper.loop(Looper.java:130)
08-13 23:39:18.017: E/Servicio Rest(6395): 	at android.app.ActivityThread.main(ActivityThread.java:3835)
08-13 23:39:18.017: E/Servicio Rest(6395): 	at java.lang.reflect.Method.invokeNative(Native Method)
08-13 23:39:18.017: E/Servicio Rest(6395): 	at java.lang.reflect.Method.invoke(Method.java:507)
08-13 23:39:18.017: E/Servicio Rest(6395): 	at com.android.internal.os.ZygoteInit$MethodAndArgsCaller.run(ZygoteInit.java:847)
08-13 23:39:18.017: E/Servicio Rest(6395): 	at com.android.internal.os.ZygoteInit.main(ZygoteInit.java:605)
08-13 23:39:18.017: E/Servicio Rest(6395): 	at dalvik.system.NativeStart.main(Native Method)