--- zic.c	2011-03-09 20:41:27.000000000 +0100
+++ zicx.c	2011-08-25 16:09:04.000000000 +0200
@@ -262,6 +262,17 @@ static int		typecnt;
 #define YR_MAXIMUM	1
 #define YR_ONLY		2
 
+/*
+** follow rules, added by Alois Treindl August 2011
+** Zones may end with a line: 0  follow  zone_name
+** which the parser will represent with FOLLOW_MARK in z_gmtoff,
+** and the zone name in z_rule.
+** Before the call to outzone() the zone and its follow zone will be
+** patched together, so that outzone() sees a regular zone array.
+** To keep zone files readable, follow rules cannot be used recursively.
+*/
+#define FOLLOW_MARK	999999
+
 static struct rule *	rules;
 static int		nrules;	/* number of rules */
 
@@ -589,7 +600,48 @@ _("%s: More than one -L option specified
 		*/
 		for (j = i + 1; j < nzones && zones[j].z_name == NULL; ++j)
 			continue;
-		outzone(&zones[i], j - i);
+		if (zones[j -1].z_gmtoff == FOLLOW_MARK) {
+		  /* copy zone and follow zone into one new array */
+		  int	k,n,m, nrows;
+                  struct zone *xzones, *zp;
+		  nrows = j - i - 1;
+		  zp = &zones[j - 1];	/* line with the follow rule */
+	          xzones = (struct zone *) (void *) emalloc((int) (nrows * sizeof *xzones));
+		  for (k = 0; k < nrows; k++)
+		    xzones[k] = zones[i + k];
+                  /* now find the follow zone in array zones[] */
+		  for (m = 0; m < nzones; m++)  {
+		    if (zones[m].z_name != NULL && strcmp(zp->z_rule, zones[m].z_name) == 0) break;
+		  }
+		  if (m == nzones) {  /* error, follow zone not found */
+		    char *cp;
+		    cp = emalloc(80 + strlen(zp->z_rule) + strlen(zones[i].z_name));;
+		    sprintf(cp, "For zone %s follow zone %s not found, no zonefile created.", zones[i].z_name, zp->z_rule);
+		    eat(zp->z_filename, zp->z_linenum);
+		    error(cp);
+		    ifree(cp);
+		    ifree((void *)xzones);
+		  }
+		  /* now find the next date in the follow zone */
+		  for (n = m + 1; n < nzones; n++) {
+		    if (zp->z_untiltime < zones[n].z_untiltime) break;
+		  }
+		  /* missing errorcode for case n == nzones,
+		   * assume we are still in same follow zone.
+                   * The follow zone part we need starts at zones[n].
+		   * Now find where follow zone ends, will be m.
+		   */
+		  for (m = n; m < nzones && zones[m].z_name == NULL; ++m)
+		    continue;
+	          xzones = (struct zone *) (void *) erealloc((char *) xzones, (int) ((nrows + m - n) * sizeof *xzones));
+		  for (k = 0; k <  m - n; k++)
+		    xzones[nrows + k] = zones[n + k];
+                  nrows += m - n;
+		  outzone(&xzones[0], nrows);
+		  ifree((void *) xzones);
+		} else {
+		  outzone(&zones[i], j - i);
+		}
 	}
 	/*
 	** Make links.
@@ -784,7 +836,7 @@ associate(void)
 	}
 	for (i = 0; i < nzones; ++i) {
 		zp = &zones[i];
-		if (zp->z_nrules == 0) {
+		if (zp->z_nrules == 0 && zp->z_gmtoff != FOLLOW_MARK) {
 			/*
 			** Maybe we have a local standard time offset.
 			*/
@@ -1079,11 +1131,23 @@ const int		iscont;
 			return FALSE;
 		}
 	}
-	z.z_rule = ecpyalloc(fields[i_rule]);
-	z.z_format = ecpyalloc(fields[i_format]);
-	if (max_format_len < strlen(z.z_format))
-		max_format_len = strlen(z.z_format);
-	hasuntil = nfields > i_untilyear;
+	/* check for 0 follow zonename
+        ** zonename must contain at least one /, and follow must be
+	* 'follow' or an abbreviation thereof.
+	 */
+	if (z.z_gmtoff == 0 && strchr(fields[i_format], '/') != NULL
+	&& itsabbr(fields[i_rule], "follow")) {
+		z.z_gmtoff = FOLLOW_MARK;
+		z.z_rule = ecpyalloc(fields[i_format]);
+		z.z_format = "";
+		hasuntil = FALSE;	/* no continue of zone now */
+	} else {
+		z.z_rule = ecpyalloc(fields[i_rule]);
+		z.z_format = ecpyalloc(fields[i_format]);
+		if (max_format_len < strlen(z.z_format))
+			max_format_len = strlen(z.z_format);
+		hasuntil = nfields > i_untilyear;
+	}
 	if (hasuntil) {
 		z.z_untilrule.r_filename = filename;
 		z.z_untilrule.r_linenum = linenum;