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diff --git a/indra/llcommon/lleventdispatcher.h b/indra/llcommon/lleventdispatcher.h
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+/**
+ * @file   lleventdispatcher.h
+ * @author Nat Goodspeed
+ * @date   2009-06-18
+ * @brief  Central mechanism for dispatching events by string name. This is
+ *         useful when you have a single LLEventPump listener on which you can
+ *         request different operations, vs. instantiating a different
+ *         LLEventPump for each such operation.
+ * 
+ * $LicenseInfo:firstyear=2009&license=viewerlgpl$
+ * Second Life Viewer Source Code
+ * Copyright (C) 2010, Linden Research, Inc.
+ * 
+ * This library is free software; you can redistribute it and/or
+ * modify it under the terms of the GNU Lesser General Public
+ * License as published by the Free Software Foundation;
+ * version 2.1 of the License only.
+ * 
+ * This library 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
+ * Lesser General Public License for more details.
+ * 
+ * You should have received a copy of the GNU Lesser General Public
+ * License along with this library; if not, write to the Free Software
+ * Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA  02110-1301  USA
+ * 
+ * Linden Research, Inc., 945 Battery Street, San Francisco, CA  94111  USA
+ * $/LicenseInfo$
+ */
+
+#if ! defined(LL_LLEVENTDISPATCHER_H)
+#define LL_LLEVENTDISPATCHER_H
+
+#include <string>
+#include <map>
+#include <boost/function.hpp>
+#include <boost/bind.hpp>
+#include <boost/iterator/transform_iterator.hpp>
+#include <typeinfo>
+#include "llevents.h"
+
+class LLSD;
+
+/**
+ * Given an LLSD map, examine a string-valued key and call a corresponding
+ * callable. This class is designed to be contained by an LLEventPump
+ * listener class that will register some of its own methods, though any
+ * callable can be used.
+ */
+class LL_COMMON_API LLEventDispatcher
+{
+public:
+    LLEventDispatcher(const std::string& desc, const std::string& key);
+    virtual ~LLEventDispatcher();
+
+    /// Accept any C++ callable, typically a boost::bind() expression
+    typedef boost::function<void(const LLSD&)> Callable;
+
+    /**
+     * Register a @a callable by @a name. The optional @a required parameter
+     * is used to validate the structure of each incoming event (see
+     * llsd_matches()).
+     */
+    void add(const std::string& name,
+             const std::string& desc,
+             const Callable& callable,
+             const LLSD& required=LLSD());
+
+    /**
+     * Special case: a subclass of this class can pass an unbound member
+     * function pointer without explicitly specifying the
+     * <tt>boost::bind()</tt> expression.
+     */
+    template <class CLASS>
+    void add(const std::string& name,
+             const std::string& desc,
+             void (CLASS::*method)(const LLSD&),
+             const LLSD& required=LLSD())
+    {
+        addMethod<CLASS>(name, desc, method, required);
+    }
+
+    /// Overload for both const and non-const methods
+    template <class CLASS>
+    void add(const std::string& name,
+             const std::string& desc,
+             void (CLASS::*method)(const LLSD&) const,
+             const LLSD& required=LLSD())
+    {
+        addMethod<CLASS>(name, desc, method, required);
+    }
+
+    /// Convenience: for LLEventDispatcher, not every callable needs a
+    /// documentation string.
+    template <typename CALLABLE>
+    void add(const std::string& name,
+             CALLABLE callable,
+             const LLSD& required=LLSD())
+    {
+        add(name, "", callable, required);
+    }
+
+    /// Unregister a callable
+    bool remove(const std::string& name);
+
+    /// Call a registered callable with an explicitly-specified name. If no
+    /// such callable exists, die with LL_ERRS. If the @a event fails to match
+    /// the @a required prototype specified at add() time, die with LL_ERRS.
+    void operator()(const std::string& name, const LLSD& event) const;
+
+    /// Extract the @a key value from the incoming @a event, and call the
+    /// callable whose name is specified by that map @a key. If no such
+    /// callable exists, die with LL_ERRS. If the @a event fails to match the
+    /// @a required prototype specified at add() time, die with LL_ERRS.
+    void operator()(const LLSD& event) const;
+
+    /// @name Iterate over defined names
+    //@{
+    typedef std::pair<std::string, std::string> NameDesc;
+
+private:
+    struct DispatchEntry
+    {
+        DispatchEntry(const Callable& func, const std::string& desc, const LLSD& required):
+            mFunc(func),
+            mDesc(desc),
+            mRequired(required)
+        {}
+        Callable mFunc;
+        std::string mDesc;
+        LLSD mRequired;
+    };
+    typedef std::map<std::string, DispatchEntry> DispatchMap;
+
+public:
+    /// We want the flexibility to redefine what data we store per name,
+    /// therefore our public interface doesn't expose DispatchMap iterators,
+    /// or DispatchMap itself, or DispatchEntry. Instead we explicitly
+    /// transform each DispatchMap item to NameDesc on dereferencing.
+    typedef boost::transform_iterator<NameDesc(*)(const DispatchMap::value_type&), DispatchMap::const_iterator> const_iterator;
+    const_iterator begin() const
+    {
+        return boost::make_transform_iterator(mDispatch.begin(), makeNameDesc);
+    }
+    const_iterator end() const
+    {
+        return boost::make_transform_iterator(mDispatch.end(), makeNameDesc);
+    }
+    //@}
+
+    /// Fetch the Callable for the specified name. If no such name was
+    /// registered, return an empty() Callable.
+    Callable get(const std::string& name) const;
+
+    /// Get information about a specific Callable
+    LLSD getMetadata(const std::string& name) const;
+
+    /// Retrieve the LLSD key we use for one-arg <tt>operator()</tt> method
+    std::string getDispatchKey() const { return mKey; }
+
+private:
+    template <class CLASS, typename METHOD>
+    void addMethod(const std::string& name, const std::string& desc,
+                   const METHOD& method, const LLSD& required)
+    {
+        CLASS* downcast = dynamic_cast<CLASS*>(this);
+        if (! downcast)
+        {
+            addFail(name, typeid(CLASS).name());
+        }
+        else
+        {
+            add(name, desc, boost::bind(method, downcast, _1), required);
+        }
+    }
+    void addFail(const std::string& name, const std::string& classname) const;
+    /// try to dispatch, return @c true if success
+    bool attemptCall(const std::string& name, const LLSD& event) const;
+
+    std::string mDesc, mKey;
+    DispatchMap mDispatch;
+
+    static NameDesc makeNameDesc(const DispatchMap::value_type& item)
+    {
+        return NameDesc(item.first, item.second.mDesc);
+    }
+};
+
+/**
+ * Bundle an LLEventPump and a listener with an LLEventDispatcher. A class
+ * that contains (or derives from) LLDispatchListener need only specify the
+ * LLEventPump name and dispatch key, and add() its methods. Incoming events
+ * will automatically be dispatched.
+ */
+class LL_COMMON_API LLDispatchListener: public LLEventDispatcher
+{
+public:
+    LLDispatchListener(const std::string& pumpname, const std::string& key);
+
+    std::string getPumpName() const { return mPump.getName(); }
+
+private:
+    bool process(const LLSD& event);
+
+    LLEventStream mPump;
+    LLTempBoundListener mBoundListener;
+};
+
+#endif /* ! defined(LL_LLEVENTDISPATCHER_H) */