Here at elsie the Central time zone seems okay; witness this excerpt from the output of "zdump -v US/Central":
 
...
US/Central  Sun Apr  4 07:59:59 2004 UTC = Sun Apr  4 01:59:59 2004 CST isdst=0
US/Central  Sun Apr  4 08:00:00 2004 UTC = Sun Apr  4 03:00:00 2004 CDT isdst=1
US/Central  Sun Oct 31 06:59:59 2004 UTC = Sun Oct 31 01:59:59 2004 CDT isdst=1
US/Central  Sun Oct 31 07:00:00 2004 UTC = Sun Oct 31 01:00:00 2004 CST isdst=0
US/Central  Sun Apr  3 07:59:59 2005 UTC = Sun Apr  3 01:59:59 2005 CST isdst=0
US/Central  Sun Apr  3 08:00:00 2005 UTC = Sun Apr  3 03:00:00 2005 CDT isdst=1
US/Central  Sun Oct 30 06:59:59 2005 UTC = Sun Oct 30 01:59:59 2005 CDT isdst=1
US/Central  Sun Oct 30 07:00:00 2005 UTC = Sun Oct 30 01:00:00 2005 CST isdst=0
US/Central  Sun Apr  2 07:59:59 2006 UTC = Sun Apr  2 01:59:59 2006 CST isdst=0
US/Central  Sun Apr  2 08:00:00 2006 UTC = Sun Apr  2 03:00:00 2006 CDT isdst=1
US/Central  Sun Oct 29 06:59:59 2006 UTC = Sun Oct 29 01:59:59 2006 CDT isdst=1
US/Central  Sun Oct 29 07:00:00 2006 UTC = Sun Oct 29 01:00:00 2006 CST isdst=0
...
 
                --ado