If there is one thing Radius should guaranty it's security, It would be very handy if additional, more secure, methods of hashing would be added.
At the moment one can choose to save password to the db either as (1)Clear text (2)MD5 or (3)Crypt.
"Clear text" for a RadiusServer is suicidal, MD5 can be cracked these days instantly.Crypt has issues as it only uses the first 8 chars in some implementation and is platform dependent (not working on Windows).
The most obvious addition for PHP may be SHA2, but this days a more brute force resistant solution exist.
And don't forget salting.