Communications Exception (-336)

When trying to connect to webmail.netscape.com via squid-2.3.STABLE1
I get a Netscape dialog box saying "Communications Exception (-336)".

There are no errors in cache.log.
The entry in access.log is

948210491.902 RELEASE FFFFFFFF 200 948210493 -1 -1 text/html -1/1 659
GET http://webmail.netscape.com/tpl/Door/Login?

Trying to access http://webmail.netscape.com/tpl/Door/Login? gives the
error.

Turning OFF the proxy in the browser settings and connecting directly
works fine.

This happens with browsers on PC, Macintosh and Unix so I can only
assume that the error lies with squid somewhere.

Any help please?

--
Mark Foster, University of Sussex Computing Service, Falmer, UK. BN1 9QJ
EMail: m.e.foster@sussex.ac.uk    -    VOICE/FAX: +44 1273 678902/271956
            -------------------------------------------------
"There are no such useless words as...'I didn't have a chance.'"
                                                         [Driving, HMSO]