http://www.presidencia.gub.uy/_web/decretos/2006/09/09_2006.htm
Uruguay's DST will be more regular from now on until otherwise decreed.  It will be scheduled to start the first Sunday of October, 02:00am ending the second Sunday of March, 02:00am.

tzdata for the file southamerica should refect this change:
Rule    Uruguay 2006    max     -       Oct     Sun>=1   2:00   1:00    S
Rule    Uruguay 2007    max     -       Mar     Sun>=8   2:00   0       -

--
Regards,
     Mauricio Campiglia

/* Tantas ventanas y tan poco tiempo... */