Many ..reading.. Request in server-status

Hi.

I'm running a few servers with Apache 2.2.3, PHP (FastCGI) on Debian Etch
and worry about a behavior of one server i monitored for the last weeks.

If i access /server-status (ExtendedStatus enabeld) i see lots of
"..reading.."-Requests "R" in the processlist, that seem to resist forever.

First i realized the problem as a kind of denial of service attack of one
single ip-adress. If i blocked the ip in the local firewall the behavior
stopped, but it seems to also happens with other connections.

I'm asking myself whats happening there and why Apache doesn't stop the
request after timeout?

I'm believing that this requests are slowing down my system and eating up my
resources. If i don't restart apache in several time periods the memory
usage will take over and server starts swapping. Once i had to reboot it
remotly cause i came too late, no memory was free anymore and nothing
reacted anymore.

I'm also wondering why this happens only on one server and not by the other
ones which are completely identical configured.

Do you have any ideas about it?

I would be glad, if anyone could give me a hint about it.

Best regards,
Oliver Treck