cal isn't localised, follows Gregorian calendar adoption of British Empire

[Sense Egbert Hofstede]

Binary package hint: bsdmainutils

When you execute the command 'cal 9 1752' you'll see that after 2 September there is 14 September. This is because that was the date the British Empire adopted the Gregorian calendar and skipped 11 days.

However, this is not correct in all countries and should be localised.
Italy, Poland, Portugal, Spain and its territories in the current US switched to the Gregorian calendar on the 4th of October 1582,
France and its territories in the current US switched on the 9th of December 1582, with the exception of Alsace and Lorraine,
the Dutch and Belgium provinces of Zeeland and Brabant and the Dutch parliament(Staten-Generaal) on 14th December 1582,
the other Southern provinces of the Low Lands, including the province of Limburg on either 20th of 21th of December 1582,
the Dutch province of Holland on the 1th of January 1583,
the Dutch province of Groningen on the 10th February of 1583 (until the summer of 1594),
the Austrian lands Brixen, Salzburg and Tirol on the 5th of October 1583,
the Austrian lands of Carinthia en Styria on the 14th of December 1583,
the Czech lands of Bohemia and Moravia on the 6th of January 1584,
Hungary on the 21th of October 1587,
Prusia on the 22th of August 1610,
the French department of Alsace with the exception of Strasbourg on the 5th of February 1682,
Denmark and Norway on the 18th of February 1700,
Sweden and Finland on the 28th of February 1700,
the Dutch provinces of Gelderland, Overijsel and Utrech on the 30th of June 1700,
the Dutch provinces of Friesland and Groningen on the 31th of December 1700,
the Dutch province of Drenthe on the 30th of April 1701,
the French department of Lorraine on the 16th of February 1760,
the American state of Alaske when it joined the USA,
Bulgaria on the 31th of March 1916,
Russia and Estonia on the 31th of January 1918,
Greece on the 9th of March 1924.
(Source: http://nl.wikipedia.org/wiki/Lijst_van_invoeringsdata_van_de_Gregoriaanse_kalender_per_land)

This list is incomplete, but it demonstrates the large differences between countries and shows that the current approach isn't correct for most of the world.

[Launchpad Janitor (janitor)]

Status changed to 'Confirmed' because the bug affects multiple users.

[Rolf Leggewie (r0lf)]

Is this possibly the source of the problem that "cal 1084" for me shows Jan 1 1084 as Monday. Whereas http://5ko.free.fr/en/year.php?y=1084&s= and other sources show it as Tuesday?