Short: random() is not random enough
From: Holger@Wunderland
Date: 990217
Type: Bug
State: Done - fixed in 3.2.8-dev.191

The key is not to use the low-order bits of the raw random number when
fitting the random number into the range (ie.: don't use %).

Description:

random() % something small is apparently not random enough. Linux' srand()
and rand() seem to deliver better results.

