Does anyone know why Time.local gives these offsets here? (+0100 is correct)

fxn@rails:~/rails/activerecord$ rvm use 1.8.7

info: Using ruby 1.8.7 p302
fxn@rails:~/rails/activerecord$ ruby -e 'p Time.local(2010); p
Time.local(1940); p Time.local(1807)'
Fri Jan 01 00:00:00 +0100 2010
Mon Jan 01 00:00:00 +0000 1940
Thu Jan 01 00:00:00 -0014 1807

fxn@rails:~/rails/activerecord$ rvm use 1.9.2

info: Using ruby 1.9.2 p0
fxn@rails:~/rails/activerecord$ ruby -e 'p Time.local(2010); p
Time.local(1940); p Time.local(1807)'
2010-01-01 00:00:00 +0100
1940-01-01 00:00:00 +0000
1807-01-01 00:00:00 -0015

Local time zone is Europe/Madrid, the TZ environment variable is empty.