diff --git a/Contrib/nsExec/nsexec.c b/Contrib/nsExec/nsexec.c
index b99d3ed8..dd6e9059 100644
--- a/Contrib/nsExec/nsexec.c
+++ b/Contrib/nsExec/nsexec.c
@@ -107,19 +107,19 @@ BOOL IsWOW64() {
  * @param cnt     [in]  the size of widebuf in wchar_t's.
  * @return true, if ASCII, false if suspected as wide.
  */
-BOOL WideConvertIfASCII(const char* ansiStr, int strLen, WCHAR* wideBuf, int cnt)
+BOOL WideConvertIfASCII(const char* ansiStr, int strLen, WCHAR* wideBuf, int cnt, BOOL OEMCP)
 {
    BOOL rval = FALSE;
    wideBuf[0] = 0;
    if (lstrlenA(ansiStr) == strLen)
    {
-      MultiByteToWideChar(CP_ACP, 0, ansiStr, -1, wideBuf, cnt);
+      MultiByteToWideChar(OEMCP ? CP_OEMCP : CP_ACP, 0, ansiStr, -1, wideBuf, cnt);
       rval = TRUE;
    }
    else
    {
       // Going to assume that it's a wide char array.
-      lstrcpyW(wideBuf, (const WCHAR*) ansiStr);
+      lstrcpynW(wideBuf, (const WCHAR*) ansiStr, cnt);
    }
 
    return rval;
@@ -307,7 +307,7 @@ params:
 #ifdef _UNICODE
         ReadFile(read_stdout, ansiBuf, sizeof(ansiBuf)-1, &dwRead, NULL);
         ansiBuf[dwRead] = 0;
-        WideConvertIfASCII(ansiBuf, dwRead, szBuf, sizeof(szBuf)/sizeof(szBuf[0]));
+        WideConvertIfASCII(ansiBuf, dwRead, szBuf, sizeof(szBuf)/sizeof(szBuf[0]), bOEM);
 #else
         ReadFile(read_stdout, szBuf, sizeof(szBuf)-1, &dwRead, NULL);
         szBuf[dwRead] = '\0';
diff --git a/Docs/src/history.but b/Docs/src/history.but
index 907759e2..b48d6fef 100644
--- a/Docs/src/history.but
+++ b/Docs/src/history.but
@@ -16,6 +16,8 @@ Released on ? ?th, 2017
 
 \b Added support for MUI_UNCONFIRMPAGE_VARIABLE (\W{http://sf.net/p/nsis/feature-requests/511}{RFE #511})
 
+\b Unicode nsExec now supports the /OEM switch (\W{http://sf.net/p/nsis/bugs/1171}{bug #1171})
+
 \S2{} Translations
 
 \b Minor French improvements (\W{http://sf.net/p/nsis/patches/221}{patch #221})