Description of problem:
useradd(1) states 


Version-Release number of selected component (if applicable):
shadow-utils-4.1.4.2-13.el6

How reproducible:
Always


Steps to Reproduce:
1. Fresh install RHEL 6
2. useradd foo
3. Observe that foo's UID value is 500.
4. man useradd
   Observe the section describing the -u option.
 
Actual results:
       -u, --uid UID
           The numerical value of the user?s ID. This value must be unique,
           unless the -o option is used. The value must be non-negative. The
           default is to use the smallest ID value greater than 999 and
           greater than every other user. Values between 0 and 999 are
           typically reserved for system accounts.


Expected results:
       -u, --uid UID
           The numerical value of the user?s ID. This value must be unique,
           unless the -o option is used. The value must be non-negative. The
           default is to use the smallest ID value greater than 499 and
           greater than every other user. Values between 0 and 499 are
           typically reserved for system accounts.


Additional info:
I see that /etc/login.defs is patched so that UID_MIN and GID_MIN are both 500 but the man page does not reflect that change. If this is an intended behavior, the man page should be fixed as well.