CvGetCaptureProperty returning -1 all the time

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When I am trying to get the frame number and Milli sec time using CvGetCaptureProperty() I am getting -1 all the time ?? I have searched a lot on the net but haven't found any solutions . Please help if anybdy has got it solved Brief Code looks like this :

CvCapture* capture = cvCaptureFromCAM(0);

while(1) { IplImage* frame = cvQueryFrame(capture);

cout << (int) cvGetCaptureProperty(capture,CV_CAP_PROP_POS_MSEC);

cvShowImage("Video_Input",frame);

if ( (cvWaitKey(10) & 255) == 27 ) break;

}