ACS 5.x does not support Dynamic IP allocation by using the IP pool feature which is available on ACS 4.X
Please check Release notes ACS 5.3
Release Notes for Cisco Secure Access Control System 5.3
http://www.cisco.com/en/US/docs/net_mgmt/cisco_secure_access_control_system/5.3/release/notes/acs_53_rn.pdf
Features Not Supported
The following features are not supported in ACS 5.3:
• The Create, Read, Update, and Delete (CRUD) operations for network device objects in REST PI.
• The Create, Read, Update, and Delete (CRUD) operations for end devices (hosts) in REST PI.
• Ability to provide IP addresses from IP address pools defined in ACS.
• Additional comparison operators for policy definitions such as full range or string and integers
matching operators.
• Instance specific configuration
• Ability to show the IP address from where the request came, in the Failed Authentications report
• Ability to authenticate the users against an external ODBC database.
• RDBMS support for synchronization of user accounts with an external database.
• Online certificate status protocol (OSCP).
• Support for on VMware installations with less than 500 GB hard disk.
• Support for VMware Tools.