> 1) Upgrade to -current; -current's com.c driver is much better than
   > the one in 1.0.  pppd in -current is also newer and (I presume)
   > better.

   com.c doesn't seem to have changed from 1.0 to -current.

It most certainly has.  Among other things, it's much less likely to
drop bits on the floor.

   > Optimizations like these allow me to get ~1630 chars/sec FTP transfers
   > over a 14.4kbps w/V.42+V.42bis modem.  My ISP uses Livingston
   > Portmasters.

   I can't seem to get -current kernel compiled, a few problems, missing header
   files. (vnd.h, vt.h, audio.h etc)

That's probably because you didn't run the new `config' program in
your compilation directory.