It gets stuck _only_ if I am root. Running su without root permission
is no problem.
As written before, If I kick out the "stty intr '^C'" from root's
.bashrc, then the second su succeeds. Running the stty command
manually in this new shell is no problem.
Can you reproduce this problem? It doesn't need XWindow or any
special user. Simply login as root on tty2, and run "su". If it
gets stuck, then you could login on tty3 and kill -9 ### the blocking