docs/wineusr: Add WINEARCH description

[André Hentschel]

gives the docs some more flavor about wow64... :)
---
 en/wineusr-running.sgml |   12 ++++++++++++
 1 files changed, 12 insertions(+), 0 deletions(-)

diff --git a/en/wineusr-running.sgml b/en/wineusr-running.sgml
index 9c5ae2f..1ec71e9 100644
--- a/en/wineusr-running.sgml
+++ b/en/wineusr-running.sgml
@@ -279,6 +279,18 @@ Path="c:\windows;c:\windows\system;e:\;e:\test;f:\"
         </para>
       </sect2>
       <sect2>
+        <title>WINEARCH</title>
+        <para>
+          Specifies the Windows architecture to support. It can be set either to
+          win32 (support only 32-bit applications), or to win64
+          (support both 64-bit applications and 32-bit ones in WoW64 mode).
+          The  architecture  supported by a given Wine prefix is set at prefix
+          creation time and cannot be changed afterwards. When running with an
+          existing prefix, Wine will refuse to start if WINEARCH doesn't match
+          the prefix architecture.
+        </para>
+      </sect2>
+      <sect2>
         <title>OSS Audio Driver Settings</title>
         <para>
           If you are using the OSS audio driver and you have multiple devices,
-- 

Best Regards, André Hentschel