Repeated use of a variadic function argument doesn't work

I have a function that tries to log stuff to the console and also to a log file, but it doesn't work. The second use of the variable length argument gives garbage written to the console. Any ideas?

    void logPrintf(const char *fmt, ...) {
        va_list ap;    // log to logfile
        va_start(ap, fmt);
        logOpen;
        vfprintf(flog, fmt, ap);
        logClose;
        va_end(ap);
        va_list ap2;   // log to console
        va_start(ap2, fmt);
        printf(fmt, ap2);
        va_end(ap2);
    }