cd hw/xfree86/os-support/linux
1)
It seems an error slipped into the patch I submitted for bug #4511.  It results
in Makefile parsing errors.  Sorry about that :(  The patch adding the necessary
'\' is included here:
--- Makefile.am 2005-10-17 09:18:58 +0200
+++
/var/tmp/portage/xorg-server-0.99.2-r1/work/xorg-server-0.99.2/hw/xfree86/os-support/linux/Makefile.am
     2005-10-30 09:47:48 +0100
@@ -4,8 +4,8 @@
 PLATFORM_PCI_SUPPORT = $(srcdir)/../shared/ia64Pci.c
 endif
 if LINUX_ALPHA
-PLATFORM_PCI_SUPPORT = lnx_ev56.c
-       $(srcdir)/lnx_axp.c
+PLATFORM_PCI_SUPPORT = lnx_ev56.c \
+       $(srcdir)/lnx_axp.c \
        $(srcdir)/../shared/xf86Axp.c
 endif

2)
An include file that I believe was found by the build system earlier, is not
found anymore.  (../shared/xf86Axp.h)  
--- lnx_axp.c   2005-07-03 10:53:46 +0200
+++
/var/tmp/portage/xorg-server-0.99.2-r1/work/xorg-server-0.99.2/hw/xfree86/os-support/linux/lnx_axp.c
       2005-10-30 10:13:06 +0100
@@ -9,7 +9,7 @@
 #include "os.h"
 #include "xf86.h"
 #include "xf86Priv.h"
-#include "xf86Axp.h"
+#include "shared/xf86Axp.h"

 axpDevice lnxGetAXP(void);

I believe the same problem affects lnx_ia64.c, where #include "ia64Pci.h" is
attempted, but I haven't got an ia64 to actually confirm that.  

Thanks!