[ale] memory limits for Linux servers?

[sad at ale.org (Steven A DuChene)]

While talking on the phone yesterday with a local supplier about an ATX
case I am interested in, I mentioned it is for a Linux system and he
responded with info that they have started building Linux systems since
they have been getting more requests for them. He told me about some
servers they are assembling with 4 way 400MHz Xeon processors and 2.5Gb
of main memory with RedHat 5.1 but they have been unable to get the
system to recognize more than 1Gb of memory (OH, I wish I had problems
like this with my systems! :). Anyone know of this problem? Is it true
at 2.0.whatever that is included with 5.1 and is this still true in the
newer 2.1.X kernels?
-- 
Steve DuChene              sad at ale.org