diff --git a/README.txt b/README.txt
index a33a85b218..016d60e68c 100755
--- a/README.txt
+++ b/README.txt
@@ -55,10 +55,13 @@ For X11 support, you need recent development libraries for libc,
 Pango, X11, and OpenGL. On a Debian-derived Linux distribution
 (like Ubuntu), you can use the following line to grab everything:
 
-    sudo apt-get install libc6-dev libpango-1.0-dev libx11-dev
+    sudo apt-get install libc6-dev libpango1.0-dev libx11-dev libgl1-mesa-dev
+
+Note that if you are using a proprietary OpenGL driver, you should
+probably leave out the last package in the list.
 
 If your DISPLAY environment variable is set, the UI will start
-automatically:
+automatically when you run Factor:
 
   ./factor
 
diff --git a/basis/cpu/x86/64/winnt/winnt.factor b/basis/cpu/x86/64/winnt/winnt.factor
index 8091be65ae..44e8568658 100644
--- a/basis/cpu/x86/64/winnt/winnt.factor
+++ b/basis/cpu/x86/64/winnt/winnt.factor
@@ -1,7 +1,8 @@
 ! Copyright (C) 2008 Slava Pestov.
 ! See http://factorcode.org/license.txt for BSD license.
 USING: kernel layouts system math alien.c-types sequences
-compiler.cfg.registers cpu.architecture cpu.x86.assembler cpu.x86 ;
+compiler.cfg.registers cpu.architecture cpu.x86.assembler cpu.x86
+cpu.x86.assembler.operands ;
 IN: cpu.x86.64.winnt
 
 M: int-regs param-regs drop { RCX RDX R8 R9 } ;