The Mexican government has re-arranged the DST schedule of the northern part of their country to follow the DST schedule of the United States:
Mexico's Congress passed a law in December 2009, bringing the DST schedule observed by northern Mexico's border cities to be in line with the United States' DST schedule. The proposed daylight saving arrangement will affect the following areas:
Tijuana, Mexicali, Ciudad Juarez, Ojinaga, Ciudad Acuna, Piedras Negras, Anahuac, Nuevo Laredo, Reynosa, Matamoros.
The new DST schedule will see these areas move the clocks forward from 2am (02:00) to 3am (03:00) local time on the second Sunday of March, and then back from 2am (02:00) to 1am (01:00) local time on the first Sunday of November. [...]
These changes are available now in FreeBSD 8-STABLE, 7-STABLE, 6-STABLE and HEAD (and the upcoming 7.3 release). For people not following the stable track, please use the port misc/zoneinfo to update.