http://www.bay12games.com/dwarves/mantisbt/view.php?id=5994

Original code:

.text:008629BD                 mov     edi, [eax+38h]
.text:008629C0                 mov     eax, [eax+3Ch]
.text:008629C3                 mov     [esp+1Ch], eax
.text:008629C7                 cmp     edi, eax
.text:008629C9                 jnb     short loc_862A22
.text:008629CB                 jmp     short loc_8629D0
.text:008629CD                 lea     ecx, [ecx+0]
...
.text:00862A19                 add     edi, 4
.text:00862A1C                 cmp     edi, [esp+1Ch]
.text:00862A20                 jb      short loc_8629D0

Patch:

0x461dbd
8B 78 38 8B 40 3C 89 44 24 1C 3B F8
8B 78 3C 8B 40 38 89 44 24 1C 39 F8

.text:008629BD                 mov     edi, [eax+3Ch]
.text:008629C0                 mov     eax, [eax+38h]
.text:008629C3                 mov     [esp+1Ch], eax
.text:008629C7                 cmp     eax, edi

0x461dcb
EB 03 8D 49 00
83 EF 04 90 90

.text:008629CB                 sub     edi, 4
.text:008629CE                 nop
.text:008629CF                 nop

0x461e19
83 C7 04 3B 7C 24 1C 72 AE
83 EF 04 3B 7C 24 1C 73 AE

.text:00862A19                 sub     edi, 4
.text:00862A1C                 cmp     edi, [esp+1Ch]
.text:00862A20                 jnb     short loc_8629D0


You can use this script to apply the generated patch below:
http://stalkr.net/files/ida/idadif.py

----8<----
This difference file is created by The Interactive Disassembler

Dwarf_Fortress
00461DBF: 38 3C
00461DC2: 3C 38
00461DC7: 3B 39
00461DCB: EB 83
00461DCC: 03 EF
00461DCD: 8D 04
00461DCE: 49 90
00461DCF: 00 90
00461E1A: C7 EF
00461E20: 72 73