diff --git a/twander.py b/twander.py
index aeb062a..42c16d7 100755
--- a/twander.py
+++ b/twander.py
@@ -4,7 +4,7 @@
 # For Updates See:  http://www.tundraware.com/Software/twander
 
 PROGNAME = "twander"
-RCSID = "$Id: twander.py,v 2.35 2002/12/24 22:16:59 tundra Exp $"
+RCSID = "$Id: twander.py,v 2.36 2002/12/31 01:09:12 tundra Exp $"
 VERSION = RCSID.split()[2]
 
 
@@ -52,8 +52,11 @@
 # Key Assignments
 #####
 
+MOUSEBINDING = 'MOUSE'    # All mouse binding names start with this string
+
 # General Program Commands
 
+MOUSECTX  = '<ButtonRelease-3>'          # Invoke context menu
 KEYPRESS  = '<KeyPress>'                 # Any keypress (for commands)
 QUITPROG  = '<Control-q>'                # Quit the program
 READCONF  = '<Control-r>'                # Re-read the configuration file
@@ -160,7 +163,7 @@
 # Constants
 #####
 
-# General constants
+# General Constants
 
 KB            = 1024      # 1 KB constant
 MB            = KB * KB   # 1 MB constant
@@ -169,8 +172,24 @@
 POLLINT       = 20        # Interval (ms) the poll routine should run
 REFRESHINT    = 3000      # Interval (ms) for automatic refresh
 
+# Key & Button Event Masks
 
-# Stat-related
+ShiftMask     = (1<<0)
+LockMask      = (1<<1)
+ControlMask   = (1<<2)
+Mod1Mask      = (1<<3)
+Mod2Mask      = (1<<4)
+Mod3Mask      = (1<<5)
+Mod4Mask      = (1<<6)
+Mod5Mask      = (1<<7)
+Button1Mask   = (1<<8)
+Button2Mask   = (1<<9)
+Button3Mask   = (1<<10)
+Button4Mask   = (1<<11)
+Button5Mask   = (1<<12)
+
+
+# Stat-Related Constants
 
 # Permissions
 
@@ -204,9 +223,9 @@
 # General Literals
 #####
 
-COMMANDMENU = 'Commands'      # Title for Command Menu button
-DIRMENU     = 'Directories'   # Title for Directory Menu button
-PSEP        = os.sep          # Character separating path components
+COMMANDMENU   = 'Commands'      # Title for Command Menu button
+DIRMENU       = 'Directories'   # Title for Directory Menu button
+PSEP          = os.sep          # Character separating path components
 
 
 #####
@@ -254,18 +273,18 @@
 
 # Errors
 
-eBADCFGLINE = "Bogus Configuration Entry In Line %s: %s"
-eBADENVVBL  = "Environment Variable %s In Line %s Not Set: %s"
+eBADCFGLINE = "Bogus Configuration Entry In Line %s:\n\n%s"
+eBADENVVBL  = "Environment Variable %s In Line %s Not Set:\n\n%s"
 eBADROOT    = " %s Is Not A Directory"
 eDIRRD      = "Cannot Open Directory : %s  ---  Check Permissions."
-eDUPKEY     = "Found Duplicate Command Key '%s' In Line %s: %s"
+eDUPKEY     = "Found Duplicate Command Key '%s' In Line %s:\n\n%s"
 eERROR      = "ERROR"
 eINITDIRBAD = "Cannot Open Starting Directory : %s - Check Permissions - ABORTING!."
 eOPEN       = "Cannot Open File: %s"
-eREDEFVAR   = "Variable %s Redefined In Line %s: %s"
+eREDEFVAR   = "Variable %s Redefined In Line %s:\n\n%s"
 eTOOMANY    = "You Can Only Specify One Starting Directory."
-eUNDEFVBL   = "Undefined Variable %s Referenced In Line %s: %s"
-eVBLTOODEEP = "Variable Definition Nested Too Deeply At Line %s: %s"
+eUNDEFVBL   = "Undefined Variable %s Referenced In Line %s:\n\n%s"
+eVBLTOODEEP = "Variable Definition Nested Too Deeply At Line %s:\n\n%s"
 
 # Information
 
@@ -283,6 +302,7 @@
 
 wCMDKEY     = "Configuration File Entry For: \'%s\' Has No Command Key Defined."
 wCONFOPEN   = "Cannot Open Configuration File:\n%s\n\n%s"
+wMOUSEBIND  = "Cannot Rebind A Mouse Button Combination.\nIgnoring Line %s:\n\n%s"
 wNOCMDS     = "Running With No Commands Defined!"
 wSYMBACK    = " Symbolic Link %s Points Back To Own Directory"
 wWARN       = "WARNING"
@@ -376,7 +396,8 @@
     # These may be overriden in the configuration file
     # parsing process.
 
-    UI.KeyBindings = {"KEYPRESS":KEYPRESS,
+    UI.KeyBindings = {"MOUSECTX":MOUSECTX,
+                      "KEYPRESS":KEYPRESS,
                       "QUITPROG":QUITPROG,
                       "READCONF":READCONF,
                       "REFRESH":REFRESH,
@@ -568,10 +589,14 @@
             sys.exit(1)
             
         # Distinguish between internal program variables and
-        # user-defined variables and act accordingly
+        # user-defined variables and act accordingly.
+        # We inhibit the rebinding of mouse button assignments, however.
 
         if name in UI.KeyBindings.keys():
-            UI.KeyBindings[name] = val
+            if name.startswith(MOUSEBINDING):
+                WrnMsg(wMOUSEBIND % (num, line))
+            else:
+                UI.KeyBindings[name] = val
         else:
             UI.SymTable[name] = val
 
@@ -686,7 +711,7 @@
 
 def StripPSEP(s):
 
-    if s[-1] == PSEP:
+    if s and s[-1] == PSEP:
         return s[:-1]
     else:
         return s
@@ -784,6 +809,9 @@
 
         # General Program Commands
 
+        # Bind handler to invoke context menu
+        self.DirList.bind(self.KeyBindings["MOUSECTX"], ContextMenu)
+
         # Bind handler for individual keystrokes
         self.DirList.bind(self.KeyBindings["KEYPRESS"], KeystrokeHandler)
 
@@ -995,6 +1023,22 @@
 
 
 #####
+# Event Handler: Context Menu
+#####
+
+def ContextMenu(event):
+
+    # Make sure we're not triggering on some Ctrl-Button3 combination
+    if event.state & ControlMask:
+        return
+    
+    # Popup a menu of available commands near the current mouse pointer
+    UI.CmdBtn.menu.tk_popup(UI.DirList.winfo_pointerx(), UI.DirList.winfo_pointery())
+
+# End of 'ContextMenu()'
+
+
+#####
 # Event Handler: Individual Keystrokes
 #####