At this point you should reboot your machine. When your system comes back up (assuming of course that everything went well and you still have a system), check to see what kernel you're running with uname -a. It should show you the one you just built. You also need to make sure the correct patch was installed. You can do that with dmesg | grep ACPI.*Subsystem\ revision . It should give the output: ACPI: Subsystem revision 20021212. The revision is the date the patch was released. This number will be different than mine if you are not using the 2.4.20 kernel. To look at all ACPI-related bits that were loaded/started when your system rebooted, do this: dmesg | grep ACPI . dmesg prints your boot messages and grep ACPI makes sure that only ACPI-related messages are printed.
You can also check to see what version you're using with cat /proc/acpi/info. Don't believe everything you read though. My output says that S3 is a supported state, but we already know it's not. It does give the correct version though, which is useful.