rand() in for loop in nawk returns always same value -ksh

i am troubling myself too much time now with this rand().

I want to add 1000 random numbers in an array, this is what i have so far, it works ith no error, but rand assigns all the time the same number in the arrays passing. the vary of the random numbers i want it to be from 1 to 999... any ideas whats going wrong?

btw i am running in ksh...

nawk  ' BEGIN{ 
    for (i=0; i<=999; i++) {
        srand()
        NUMBERS[i]= int(rand()*(999))
        print NUMBERS[i]
    }
}'

P.S. Not a dublicate, no other same question for ksh.

UPDATED

nawk  ' BEGIN{ 
    srand(1)
    for (i=0; i<=999; i++) {
        NUMBERS[i]= int(rand()*(999))
        XNUMBERS[i]= int(rand()*(999))
        print NUMBERS[i]
        print XNUMBERS[i]
    }
}'