Squid and listening on specific IP addresses

With Squid 1.NOVM.16 configured to listen on only one of the IP addresses
existing on the system (Solaris 2.4 for testing, will also be using 2.5)
by specifying

tcp_incoming_address 1.2.3.4
tcp_outgoing_address 1.2.3.4
udp_outgoing_address 1.2.3.4

(not the real address of course - in fact, I was using a name to make the
config more self-explanatory), while leaving udp_incoming_address undefined
since the comments in squid.conf (and discussion with James Grinter)
indicate that while the incoming and outgoing TCP addresses can be the same,
the UDP addresses must be different.

icpHandleUdp: FD 16 recvfrom: (11) Resource temporarily unavailable

in cache.log, after the pause following the "FD n Closing xxx connection"
messages, before the "Restarting Squid Cache" message.

I've not received this message before, but it happens every time when I
configure Squid to listen only on a specific address.

Does anyone else see this, or have an explanation for it?

Also, though I thought it was a one-off until doing some tests just now
to confirm the details of the problem above, if I HUP the server I
frequently see

ftpget server failing too rapidly
WARNING: FTP access is disabled!

when it attempts to resume normal service, though there *does* appear to be
an ftpget process running which is a child of the Squid process... (and
FTP requests via Squid *do* work in that situation).

Maybe pure chance, but at the moment it looks like the ftpget problem
happens consistently the first time Squid is HUP'd after starting it, but
that ftpget starts up fine (or continues running? sometimes it looks like
the old one continues and a new one is started) whenever Squid is HUP'd
subsequently.

Again, does anyone else see this (in particular, see it when listening
on a specific IP address and not in other cases)? Explanations?

Simply removing the xxx_xxx_address definitions mentioned above is sufficient
to get rid of both these problems; not a solution for me, but it serves to
confirm that using those directives is somehow related to the problems, not
pure coincidence.

                                John Line

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