diff -r 88ca50b8e7f7 config.def.h
--- a/config.def.h	Fri Nov 02 23:19:56 2012 +0100
+++ b/config.def.h	Sat Nov 03 03:12:12 2012 +0100
@@ -2,7 +2,7 @@
 
 /* appearance */
 static char font[] = "Liberation Mono:pixelsize=12:antialias=false:autohint=false";
-static unsigned int borderpx = 2;
+static int borderpx = 2;
 static char shell[] = "/bin/sh";
 
 /* double-click timeout (in milliseconds) between clicks for selection */
diff -r 88ca50b8e7f7 st.c
--- a/st.c	Fri Nov 02 23:19:56 2012 +0100
+++ b/st.c	Sat Nov 03 03:12:12 2012 +0100
@@ -72,8 +72,6 @@
 #define ATTRCMP(a, b) ((a).mode != (b).mode || (a).fg != (b).fg || (a).bg != (b).bg)
 #define IS_SET(flag) (term.mode & (flag))
 #define TIMEDIFF(t1, t2) ((t1.tv_sec-t2.tv_sec)*1000 + (t1.tv_usec-t2.tv_usec)/1000)
-#define X2COL(x) (((x) - borderpx)/xw.cw)
-#define Y2ROW(y) (((y) - borderpx)/xw.ch)
 
 #define VT102ID "\033[?6c"
 
@@ -404,6 +402,9 @@
 static char *usedfont = NULL;
 static int usedfontsize = 0;
 
+static int X2COL(int x) { x -= borderpx; x /= xw.cw; return LIMIT(x, 0, term.col-1); }
+static int Y2ROW(int y) { y -= borderpx; y /= xw.ch; return LIMIT(y, 0, term.row-1); }
+
 ssize_t
 xwrite(int fd, char *s, size_t len) {
 	size_t aux = len;