Problem: strace -ff fails on 2.4.21-rc1

Is this a bug or a feature? Machine only has 1 CPU, if that makes
any difference:

# strace -q -o minicom.trc -tt -ff minicom
upeek: ptrace(PTRACE_PEEKUSER, ... ): Operation not permitted
detach: ptrace(PTRACE_CONT, ...): Operation not permitted
Device /dev/ttyS1 lock failed: No child processes.
# uname -a
Linux d2 2.4.21-rc1 #1 SMP Wed May 7 06:05:31 EDT 2003 i686 unknown

(Ignore that minicom error message about the lock failing -- that's
a separate problem...)