Hi,
I created an account guest to test password aging.
The aging info of this account is following:
chage -l guest
Last password change : Nov 01, 2010
Password expires : Jan 30, 2011
Password inactive : never
Account expires : never
Minimum number of days between password change : 76
Maximum number of days between password change : 90
Number of days of warning before password expires : 14
However, I'm able to change my password when logged in as guest
as many times I want the same day, even if minimum number of days
between password change is set to a non-zero value.