FreeBSD 4.0, weird su behavior

[Robert Watson]

sleipnir:/afs/andrew/usr4/rnw> su
Password:
_su: Result too large
_su: Trying to start from "/root"
sleipnir:~#

(have tokens)

  Robert N Watson 

robert at fledge.watson.org              http://www.watson.org/~robert/
PGP key fingerprint: 03 01 DD 8E 15 67 48 73  25 6D 10 FC EC 68 C1 1C

Carnegie Mellon University            http://www.cmu.edu/
TIS Labs at Network Associates, Inc.  http://www.tis.com/
SafePort Network Services             http://www.safeport.com/