I get the "xmit logic failed" messages too.

It's on a MicroVAX-II running diskless.  Ethernet is DEQNA, not DELQA.
Visible symptoms are that the message appears on the console,
especially during heavy NFS traffic (eg, "make build" - yes, I'm crazy
enough to "make build" on a diskless uVAX-II).  It's possible that the
network goes out to lunch briefly; in fact, I'd expect it - but I've
never had it lock up on me; it's always come back to life on its own.
The machine is slow enough that I might well not notice if the network
went out for a second or so, even if I were using it actively at the
time.

This is with (everything built from) 2000-02-19 sources (1.4T) with a
few patches, none of which touch arch/vax or dev/qbus or anything else
that looks to me as though it should be related.

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