diff -Naur a/parsetime.y b/parsetime.y
--- a/parsetime.y	2005-08-05 03:31:04.000000000 +0000
+++ b/parsetime.y	2007-11-23 19:39:29.000000000 +0000
@@ -4,12 +4,15 @@
 #include <string.h>
 #include <stdio.h>
 #include "parsetime.h"
+#include "at.h"
+#include "panic.h"
 
 #define YYDEBUG 1
 
 static const char *svnid = "$Id$";
 struct tm exectm;
 static int isgmt;
+static char *tz = NULL;
 static int yearspec;
 static int time_only;
 
@@ -170,6 +173,12 @@
 timezone_name	: UTC
 		    {
 			isgmt = 1;
+			if (getenv("TZ")) {
+			    tz = (char *) mymalloc(strlen(getenv("TZ")) + 1);
+			    strcpy(tz, getenv("TZ"));
+			}
+			if (setenv("TZ", "UTC0", 1) == -1)
+			    panic("Virtual memory exhausted");
 		    }
 		;
 
@@ -502,9 +511,13 @@
 	if (exectime == (time_t)-1)
 	    return 0;
 	if (isgmt) {
-	    exectime -= timezone;
-	    if (currtm.tm_isdst && !exectm.tm_isdst)
-		exectime -= 3600;
+	    if (tz) {
+		if (setenv("TZ", tz, 1) == -1)
+		    panic("Virtual memory exhausted");
+		free(tz);
+	    }
+	    else
+		unsetenv("TZ");
 	}
 	if (exectime < currtime)
 		panic("refusing to create job destined in the past");