Using keybind and action to translate/simulate one keystroke into another keystroke?

[mpb]

Hi openbox at icculus.org,

I have been using Openbox for 6 months to a year.  Thus far I have
been able to configure Openbox to do just about everything I want it
to.

Prior to today, I had been using W-Left and W-Right to switch desktops.

    <keybind key="W-Left">
      <action name="DesktopLeft">
        <wrap>no</wrap>
      </action>
    </keybind>
    <keybind key="W-Right">
      <action name="DesktopRight">
        <wrap>no</wrap>
      </action>
    </keybind>

Today I realized it would be more efficient to use W-j and W-k
instead, as I would not have to move my right hand to the arrow keys.
Easy enough to do - I just added the following:

    <keybind key="W-j">
      <action name="DesktopLeft">
        <wrap>no</wrap>
      </action>
    </keybind>
    <keybind key="W-k">
      <action name="DesktopRight">
        <wrap>no</wrap>
      </action>
    </keybind>

I immediately realized that I would also like to be able to press W-L
and W-; to issue PageUp and PageDown keystrokes.  I could then switch
desktops and issue PageUp and PageDown keystrokes without moving my
right hand from the home row.  Is there someway to get Openbox to
generate simulated keystrokes in response to other specified
keystrokes?  Or perhaps there is some other, easy, non-Openbox way to
do this in X Windows?

Many thanks,

-mpb