Original Link: http://www.ehow.com/how_4812793_password-complexity-requirements-windows-xp.html#ixzz32PEZAbOn
When you create a new account in Windows XP, you choose a username and a password, which must be a certain length. If you want to get rid of this requirement or change the required complexity for new passwords, you can log on to your computer as an administrator and adjust the policy.
Instructions
1. Log on to your computer with an account that has administrative privileges.
2. Open the Start menu and click on "Control Panel."
3. Double-click on "Administrative Tools."
4. Double-click on "Local Security Policy." A new window will open with all of your computer's current security options.
5. Expand the "Account Policies" menu and click on "Password Policy."
6. Double-click on "Minimum password length" and enter a new requirement for passwords. Click "OK" to save the changes. All new passwords must now meet that requirement.