Manuel Bouyer <bouyer@antioche.lip6.fr>  wrote:
 > > Initially I used an mtu of '296' and started seeing the problem. So I
 > > bumped it down to 250 out of curiosity ... 
 > > 
 > > Later I bumped the mtu up to '502' (some random number higher than 250)
 > > and it all works fine.
 > > 
 > > So what am I missing? Shouldn't this all be independant of the mtu/mru?
 > > Or is there some sysctl I'm missing?
 > 
 > Maybe it's just that the other (ppp) end doesn't propely fragment big packets ?

The other end is a DMS-500 phone switch that I have no control of. 

 > Did you try to turn on path MTU discovery on both host ?
 > sysctl -w net.inet.ip.mtudisc=1

you mean my jornada running pppd and the 20 hop away machine with
sshd?  or you mean both ends of the ppp connection?  

Either way, I didn't. no.  I can try setting that on at least the 
jornada.