updated for version 7.3.343
Problem:    No mouse support for urxvt.
Solution:   Implement urxvt mouse support, also for > 252 columns.  (Yiding
            Jia)
diff --git a/src/keymap.h b/src/keymap.h
index 16d128a..8ec0093 100644
--- a/src/keymap.h
+++ b/src/keymap.h
@@ -92,13 +92,13 @@
  */
 #define KS_TEAROFF		244
 
-/* used for JSB term mouse */
+/* Used for JSB term mouse. */
 #define KS_JSBTERM_MOUSE	243
 
-/* used a termcap entry that produces a normal character */
+/* Used a termcap entry that produces a normal character. */
 #define KS_KEY			242
 
-/* Used for the qnx pterm mouse */
+/* Used for the qnx pterm mouse. */
 #define KS_PTERM_MOUSE		241
 
 /* Used for click in a tab pages label. */
@@ -107,6 +107,9 @@
 /* Used for menu in a tab pages line. */
 #define KS_TABMENU		239
 
+/* Used for the urxvt mouse. */
+#define KS_URXVT_MOUSE		238
+
 /*
  * Filler used after KS_SPECIAL and others
  */