From Bugzilla Helper:
User-Agent: Mozilla/4.76 [en] (X11; U; Linux 2.4.2-2 i686; Nav)

Description of problem:
from /var/log/mgetty.ttyS1.log
05/09 12:48:47 yS1   waiting for line to clear (VTIME), read:
05/09 12:48:47 yS1  tcgetattr failed: Input/output error
05/09 12:48:47 yS1  tcsetattr failed: Input/output error
05/09 12:48:47 yS1  tcsetattr failed: Input/output error
05/09 12:48:47 yS1   removing lock file
05/09 12:48:47 yS1  waiting...
05/09 12:48:47 yS1    select returned 1
05/09 12:48:47 yS1   checking lockfiles, locking the line
05/09 12:48:47 yS1   makelock(ttyS1) called
05/09 12:48:47 yS1   do_makelock: lock='/var/lock/LCK..ttyS1'
05/09 12:48:47 yS1   lock made
05/09 12:48:47 yS1  wfr: waiting for ``RING''
05/09 12:48:47 yS1   got:
05/09 12:48:47 yS1  mdm_read_byte: read returned 0: Success
05/09 12:48:47 yS1  wfr: error in read(): Success
05/09 12:48:47 yS1   wfr: rc=-1, drn=0
05/09 12:48:47 yS1  ringback: phone stopped after 0 RINGs, waiting for
re-ring
05/09 12:48:47 yS1  wfr: waiting for ``RING''
05/09 12:48:47 yS1   got:
05/09 12:48:47 yS1  mdm_read_byte: read returned 0: Success
05/09 12:48:47 yS1  wfr: error in read(): Success
05/09 12:48:47 yS1   wfr: rc=-1, drn=0
05/09 12:48:47 ##### missed ringback!

How reproducible:
Always

Steps to Reproduce:
1.start mgetty, it works
2.start pppd
3.mgetty loops
	

Additional info: