my guess is use mt_rand(min, max)
either use mt_rand() for each of the 7 digits, then combine them together, or use 1 mt_rand() for the whole thing (ie. mt_rand(1000000,9999999), if it allows numbers that large). I\'m a n00b myself, so don\'t assume this is the best way, because most likely it isnt. This should work though:
[php:1:c904f12a77]<?php
$array = array(mt_rand(1, 9), mt_rand(1, 9), mt_rand(1, 9), mt_rand(1, 9), mt_rand(1, 9), mt_rand(1, 9), mt_rand(1, 9));
$random = implode(\"\",$array);
echo $random;
?>[/php:1:c904f12a77]