🚀 go-pugleaf

First, a description of my setup

        80386-40, no co-pro
        4Mb RAM
        IDE HD, single controller, ext2 fs
        vanilla serial board, 16450 uarts
        ALPHA-pl14{p,x,z} pl15
        gcc 2.5.7, libc 4.5.8, ld.so 1.3
        net2debugged, latest 'route' from nic.funet.fi

I have spoken to several people, and followed some discussion in the
linux newsgroups, and it seems that very few people (if any) have
SLIP successfully working with any kernels after about pl14u (it
definitely broke somewhere between u and x inclusive).

Most people seem to have common symptoms: connecting and setting up
the interface working fine, but tcp connections mysteriously 'dying'
after a certain amount of time and/or data transfer.  I put my
circumstances, since they seem to be fairly typical, although
others may differ slightly, particularly some people seem to get
tcp leak messages, whereas others do not.

For me, tcp connections will mysteriously stop trasmitting data. This is
intermittent with 'telnet' and 'rlogin', and seemingly better (although
perhaps this is only an illusion) with pl14z and pl15 over pl14x. 'ftp'
connections, however, will *always* die after transferring <25k of data.
They do not disconnect, but data ceases to come through (netstat still
shows 'ESTABLISHED').  This only occurs when sending to the Linux box,
both remote 'put's and local 'get's, tranfer the other way seems fine.
Watching the modem lights, there still seems to be activity for a short
while (up to 10s) after data stops being received - by the look of the
lights, traffic both ways. After this, all data on that connection
ceases, although other conections continue to operate correctly.

There are no problems with loopback.
This is observed with a completely unloaded machine, and no other inet
processes running.
'route' and 'ifconfig' seem to show normal entries.
The same problem exists with pl14x, pl14z and pl15.
None of these problems existed with pl14p or pl14t.

So, I ask:

Is this a known problem? Is there a fix? Do any people have SLIP
working flawlessly under pl15?

Any help appreciated.

 - Mike