Actually in an open Cminor tuning C G C G C Eb (with capo at 5)

After the intro (which you are welcome to if you want it tabbed but it just falls under your fingers when tuned that way) it's pretty much like this to my ears

Verse

050000
x30000
x10000
x02020 (or x02320 to x02300 which I like as an alternate)

Chorus

050000
508000
x02020 (or x02320 )

  
  --2P0----------------------------------
  ------0H2H3P0-----------0--------------
  -------------------0H3-----------0-----
  ---------------3H5-----------------0---
  ---------------------------------------
  -0----------------------------0------0-  PLAYED TWICE THEN
  
  
  -0------------------
  ---2----------------
  -----3H0-----0------
  ---------3S5----0---
  -0------------------
  ------------------0- ETC
  
  BASS NOTES ETC PROBABLY NEED ADDING
  

This is one that I worked out myself once I knew it was open Cm so it may differ from the way he plays it.

If you ever want any help on what tunings he uses (usually open C!) there is an excellent resource at Wee Guitar with an incredibly helpful guy called Steve there who will send you stuff through on an Excel file or a bitmap. There is a little animation and tune on the front of the site which shows many of the shapes he tends to use in many of his songs.