cannot create core dump file?

[Qin Zhen]

Hi all,
i attemp to create core dump file since i encountered segmentation fault
error.
i have followed the steps in doc/bug, i.e.
./configure --enable--developer
make
make install
ulimit -c unlimited

then i ran the daemon using './radiusd -XXX' under /usr/local/radius/sbin as 
my
current directory.but afterwards there's no core dump file generated in my 
currenct dir. how
and where can i get the core dump file? any advise? thanks in advance.

regards,
Pang KW