Send the Authorization header with every request. You don't have to wait for the server to challenge you (and for those of you who think that, recall that HTTP is a stateless protocol). From RFC 2616, Section 14.8 (I added the emphasis):
A user agent that wishes to authenticate itself with a server--usually, but not necessarily, after receiving a 401 response--does so by including an Authorization request-header field with the request.
You don't have to force LWP to do it; it sounds like the ATOM client needs to know to do it.
It's difficult to point to any concrete fixes without code though.
Update: added the extract from RFC 2616
In reply to Re: Forcing LWP authentication
by brian_d_foy
in thread Forcing LWP authentication
by drewbie
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