- (NSDate*) convertToUTC:(NSDate*)sourceDate
{
    NSTimeZone* currentTimeZone = [NSTimeZone localTimeZone];
    NSTimeZone* utcTimeZone = [NSTimeZone timeZoneWithAbbreviation:@"UTC"];

    NSInteger currentGMTOffset = [currentTimeZone secondsFromGMTForDate:sourceDate];
    NSInteger gmtOffset = [utcTimeZone secondsFromGMTForDate:sourceDate];
    NSTimeInterval gmtInterval = gmtOffset - currentGMTOffset;

    NSDate* destinationDate = [[[NSDate alloc] initWithTimeInterval:gmtInterval sinceDate:sourceDate] autorelease];
    return destinationDate;
}