Hi,
 
My source files under sys/dev/acpi/acpica/Subsystem were caught up
with acpica-unix-20030228.tar.gz, and it works fine for me.
  
 I have put that patch at:
     http://www.ann.hi-ho.ne.jp/~kanaoka/acpica-20030228.diff.gz

	% /usr/bin/md5 acpica-20030228.diff.gz
	MD5 (acpica-20030228.diff.gz) = b1199146d456b8f330f111b3224c3dfb

You can try it like below:
 
  	# cd /usr/src
  	# zcat /somewhere/acpica-20030228.diff.gz | patch -p1 -E
 	# cd /sys/arch/i386/conf
  	# config your-config;cd ../compile/your-config
 	# make depend;make;make install
 
You can find chang log for ACPI CA code at:
    http://developer.intel.com/technology/iapc/acpi/downloads/CHANGES.txt
 
If you are interested in it,How about trying it?
 
Best Regards!
---
  Masanori Kanaoka	kanaoka@ann.hi-ho.ne.jp