ContextEvents and Tkinter

[cuso]

I have one problem with the following code:

from win32com.client import constants
import win32com.client
import win32gui
import pythoncom
from Tkinter import *

class SpeechRecognition:
        def __init__(self, wordsToAdd):
        self.speaker = win32com.client.Dispatch("SAPI.SpVoice")
        self.listener = win32com.client.Dispatch("SAPI.SpSharedRecognizer")
        self.context = self.listener.CreateRecoContext()
        self.grammar = self.context.CreateGrammar()
        self.grammar.DictationSetState(0)
        self.wordsRule = self.grammar.Rules.Add("wordsRule",constants.SRATopLevel + constants.SRADynamic, 0)
        self.wordsRule.Clear()
        [ self.wordsRule.InitialState.AddWordTransition(None, word) for word in wordsToAdd ]
        self.grammar.Rules.Commit()
        self.grammar.CmdSetRuleState("wordsRule", 1)
        self.grammar.Rules.Commit()
        self.eventHandler = ContextEvents(self.context)
    def say(self, phrase):
        self.speaker.Speak(phrase)

class ContextEvents(win32com.client.getevents("SAPI.SpSharedRecoContext")):
    def OnRecognition(self, StreamNumber, StreamPosition, RecognitionType, Result):
        newResult = win32com.client.Dispatch(Result)
        globals()['fraza']=newResult.PhraseInfo.GetText()
        print "You said: ",fraza
        if fraza=='winamp':
            speechReco.say("What")
            graf.list1.delete(0,END)
            graf.list1.insert(END,fraza)
            
class App:

    def __init__(self, master):
        self.list1=Listbox(master,bg='pink',width='20',height='1',font=("Comic Sans MS",14))
        self.list1.pack(anchor=W)
        self.list1.insert(0,'Hey')


if __name__=='__main__':
    globals()['fraza']=1
    wordsToAdd = ['winamp','play']
    speechReco = SpeechRecognition(wordsToAdd)
    root=Tk()
    graf=App(root)
    root.mainloop()

Problem is with these 2 lines (41,42):
graf.list1.dele te(0,END)
graf.list1.inse rt(END,fraza)
because program stops and is not responding any more when it come to this lines. If these two lines are not in class ContextEvents, the program works fine but i need them in there. Even if I call function with this two lines from ContextEvents the program freeze.

The program must delete text and insert text 'winamp' in Tkinter Label when i say winamp in microfone. Everything works fine but when i say 'winamp' program freeze. How can i solve this problem. Please help.