Lost :with Parameter on :observe_field

I am using an :observe_field on a series of select elements. It is
pretty successful. I think I have found a bug though. When I change
the option in a select, the :with parameter is sent, the next element
is updated, and everything is good.

Processing IpController#select_technology (for 0.0.0.0 at
2007-09-2711:31:39) [POST]Session ID:
c2e7072af4526b7b7a617e526e3d161bParameters:
{"ip_info_vw_ring_technology_key"=>"1","action"=>"select_technology",
"controller"=>"ip"}

If I change the option in the first select again, quickly (2
secondslater), the action sent to the controller does not contain
the :with parameter.
Processing IpController#select_technology (for 0.0.0.0 at
2007-09-2711:31:41) [POST]Session ID:
c2e7072af4526b7b7a617e526e3d161bParameters:
{"action"=>"select_technology", "controller"=>"ip"}

If I wat a little longer between changing options (6-7 seconds),
itbehaves correctly. Is this a bug anyone else has seen?

Thanks for your help,

Christian

I have nailed this down a bit. It happens on ANY Ajax call. The
reason has something to do with the fact that I am using Apache as a
proxy server ( to get the remote_user, and for load balancing ). I
would like to use Apache, but this is obviously unacceptable. Does
anoyone have any idea why this happens?