diff --git a/common/rfb/KeyRemapper.cxx b/common/rfb/KeyRemapper.cxx
new file mode 100644
index 0000000..05f0763
--- /dev/null
+++ b/common/rfb/KeyRemapper.cxx
@@ -0,0 +1,84 @@
+/* Copyright (C) 2002-2005 RealVNC Ltd.  All Rights Reserved.
+ * 
+ * This is free software; you can redistribute it and/or modify
+ * it under the terms of the GNU General Public License as published by
+ * the Free Software Foundation; either version 2 of the License, or
+ * (at your option) any later version.
+ * 
+ * This software is distributed in the hope that it will be useful,
+ * but WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+ * GNU General Public License for more details.
+ * 
+ * You should have received a copy of the GNU General Public License
+ * along with this software; if not, write to the Free Software
+ * Foundation, Inc., 59 Temple Place - Suite 330, Boston, MA  02111-1307,
+ * USA.
+ */
+
+#include <stdio.h>
+#include <rfb/KeyRemapper.h>
+#include <rfb/Configuration.h>
+#include <rfb/LogWriter.h>
+
+using namespace rfb;
+
+static LogWriter vlog("KeyRemapper");
+
+KeyRemapper KeyRemapper::defInstance;
+
+#ifdef __RFB_THREADING_IMPL
+static Mutex mappingLock;
+#endif
+
+void KeyRemapper::setMapping(const char* m) {
+#ifdef __RFB_THREADING_IMPL
+  Lock l(mappingLock);
+#endif
+  mapping.clear();
+  while (m[0]) {
+    int from, to;
+    char bidi;
+    const char* nextComma = strchr(m, ',');
+    if (!nextComma)
+      nextComma = m + strlen(m);
+    if (sscanf(m, "0x%x%c>0x%x", &from,
+               &bidi, &to) == 3) {
+      if (bidi != '-' && bidi != '<')
+        vlog.error("warning: unknown operation %c>, assuming ->", bidi);
+      mapping[from] = to;
+      if (bidi == '<')
+        mapping[to] = from;
+    } else {
+      vlog.error("warning: bad mapping %.*s", nextComma-m, m);
+    }
+    m = nextComma;
+    if (nextComma[0])
+      m++;
+  }
+}
+
+rdr::U32 KeyRemapper::remapKey(rdr::U32 key) const {
+#ifdef __RFB_THREADING_IMPL
+  Lock l(mappingLock);
+#endif
+  std::map<rdr::U32,rdr::U32>::const_iterator i = mapping.find(key);
+  if (i != mapping.end())
+    return i->second;
+  return key;
+}
+
+
+class KeyMapParameter : public StringParameter {
+public:
+  KeyMapParameter()
+    : StringParameter("RemapKeys", "Comma-separated list of incoming keysyms to remap.  Mappings are expressed as two hex values, prefixed by 0x, and separated by ->", "") {
+    setParam(value);
+  }
+  bool setParam(const char* v) {
+    KeyRemapper::defInstance.setMapping(v);
+    return StringParameter::setParam(v);
+  }
+} defaultParam;
+
+