Caltex Australia has reported a major turnaround to a net profit after tax of A$130.4 million, or 48.3 Australian cents a share, for the first half of 2002 from a net profit after tax of A$1.2 million, or A0.5 cents a share, for the same period last year. (US$1=A$1.8) Chairman Dick Warburton attributed the turnaround…