Hello,
this is what the EOS Announcement says:
The recommended upgrade path for the Cisco AS5300 Access Server is the Cisco AS5350 and AS5400 Series universal gateways. In addition to providing the dial-up data access capabilities of the Cisco AS5300 Access Server, the Cisco AS5350 and AS5400 Series universal gateways support data, voice, fax, or wireless calls on any port at any time.
Check here for the entire announcement:
End of Sale Announcement for Cisco AS5300 Access Server
http://www.cisco.com/en/US/partner/products/hw/univgate/ps501/prod_bulletin09186a0080091ef0.html
Regards,
Georg