Bolivia may change Time Zone from GMT-04 to GMT-05 in the winter.

[Alexander Krivenyshev]

According to various news reports
Bolivia is considering to change Time Zone from GMT-04 to GMT-05 in the winter 
2009/2010 to prevent the spread of colds and the new seasonal influenza A 
strain H1N1.
It would be the first time in Bolivian history that changes the time zone. 

Analizan en Bolivia cambiar el huso horario de invierno para evitar gripes
(spanish)
http://www.adn.es/sociedad/20090616/NWS-1425-Analizan-Bolivia-invierno-horario-
cambiar.html

El Gobierno quiere frenar incremento de los resfríos cambiando el huso horario 
(spanish)
http://www.erbol.com.bo/noticia1.php?identificador=1689&bdatos=notiportada1

or
(Spanish)
http://www.worldtimezone.com/dst_news/dst_news_bolivia01.html

Alexander Krivenyshev,
http://www.worldtimezone.com