--- a/src/util.c	Wed Jun 26 14:29:02 2002 +0100
+++ b/src/util.c	Wed Jun 26 14:30:26 2002 +0100
@@ -1,7 +1,7 @@
 /*
   util.c
 
-  $Id: util.c 375 2002-03-15 10:50:33Z bears $
+  $Id: util.c 391 2002-06-26 13:30:26Z bears $
 */
 
 #if HAVE_CONFIG_H
@@ -294,14 +294,15 @@
 			     "Aug", "Sep", "Oct", "Nov", "Dec", NULL };
 
 /*
- * Calculate the difference between local time and GMT. This is INN's
- * 'always-works' method. It assumes the time differences is < 24hrs.
- * Sounds reasonable to me. It also assumes it can ignore seconds.
- * Returns GMT - localtime minutes. It will also trash the localtime/
+ * Calculate the difference between local time and GMT at GMT time t.
+ *
+ * This is INN's 'always-works' method. It assumes the time differences
+ * is < 24hrs. Sounds reasonable to me. It also assumes it can ignore seconds.
+ * Returns localtime - GMT seconds. It will also trash the localtime/
  * gmtime/etc. static buffer.
  */
 static int
-tzDiff( void )
+localTimeDiff( time_t t )
 {
     time_t now;
     struct tm local, gmt, *tm;
@@ -312,25 +313,26 @@
     if ( now < nextCalc )
 	return res;
     
-    tm = localtime( &now );
+    tm = localtime( &t );
     if ( tm == NULL )
 	return 0;
     local = *tm;
-    tm = gmtime( &now );
+    tm = gmtime( &t );
     if ( tm == NULL )
 	return 0;
     gmt = *tm;
 
-    res = gmt.tm_yday - local.tm_yday;
+    res = local.tm_yday - gmt.tm_yday;
     if ( res < -1 )
 	res = -1;		/* Year rollover? */
     else if ( res > 1 )
 	res = 1;
 
     res *= 24;
-    res += gmt.tm_hour - local.tm_hour;
+    res += local.tm_hour - gmt.tm_hour;
     res *= 60;
-    res += gmt.tm_min - local.tm_min;
+    res += local.tm_min - gmt.tm_min;
+    res *= 60;
 
     /* Need to recalc at start of next hour */
     nextCalc = now + ( 60 - local.tm_sec ) + 60 * ( 59 - local.tm_min );
@@ -338,13 +340,39 @@
     return res;
 }
 
+time_t
+Utl_mktimeGMT( struct tm *t )
+{
+#if HAVE_TIMEGM
+    return timegm( t );
+#else    
+    /*
+     * Based on the portable implementation suggested in the glibc man page
+     * for timegm.
+     */
+    time_t ret;
+    char *tz;
+
+    tz = getenv("TZ");
+    setenv("TZ", "", 1);
+    tzset();
+    ret = mktime(t);
+    if (tz)
+	setenv("TZ", tz, 1);
+    else
+	unsetenv("TZ");
+    tzset();
+    return ret;
+#endif    
+}
+
 void
 Utl_newsDate( time_t t, Str res )
 {    
     struct tm *local;
     long tzdiff, hoffset, moffset;
 
-    tzdiff = - tzDiff();
+    tzdiff = localTimeDiff( t ) / 60;
 
     local = localtime( &t );
     if ( local == NULL )
@@ -463,16 +491,13 @@
     if ( *s != '\0' && ! isspace( *s ) )
 	return (time_t) -1;
 
-    res = mktime( &tm );
+    res = Utl_mktimeGMT( &tm );
     if ( res == (time_t) -1 )
 	return res;
     
     if ( wday >= 0 && wday != tm.tm_wday )
 	return (time_t) -1;
 
-    /* Remove local time diff from res to give time as if GMT */
-    res -= tzDiff() * 60;
-
     /* And now adjust for tzoffset */
     res -= tzoffset * 60;