HPETDevice kext

This kext creates HPET device in ioreg, so you dont need(if you need) to edit DSDT to get it.
You can use it if you want to get HPET device in ioreg and are lazy to edit DSDT.
by default it uses these parametrs for HPET device (in Info.plist):

<key>base-address</key>
<integer>4275044352</integer>
<key>base-length</key>
<integer>1024</integer>
<key>irq</key>
<integer>12</integer>

which correspond to this:

Memory32Fixed (ReadWrite,
0xFED00000, // Address Base
0×00000400, // Address Length
)

I dont recommend editing irq.

The kext, for use with snow leopard.
HPETDevice.kext