Yes, it is mandatory.
See this link. The government of Karnataka ensures a holiday on May Day.
http://karnataka.com <link updated to site home>
List of 2007 Government Holidays
The Karnataka State Government has announced the list of general holidays for State Government employees for the year 2007.
Date Day Occasion
January 1 Monday Bakrid
January 15 Monday Sankranti
January 26 Friday Republic Day
January 30 Tuesday Moharum
February 16 Friday Mahashivaratri
March 19 Monday Chaandramana Ugadi
March 31 Saturday Mahaveera Jayanthi
April 6 Friday Good Friday
April 20 Friday Basaveshwara Jayanthi
May 1 Tuesday May Day
August 15 Wednesday Independence Day
September 15 Saturday Ganesh Chaturthi
October 2 Tuesday Gandhi Jayanthi
October 10 Wednesday Mahalaya amavasya
October 20 Saturday Mahanavami Ayudha Puja
November 1 Thursday Kannada Rajyotsava
November 8 Thursday Deepavali / Naraka Chaturdashi
December 21 Friday Bakrid
December 25 Tuesday Christmas
May Day is May 1 and refers to any of several holidays celebrated on this day. May 1 was a traditional springtime holiday in many pre-Christian European pagan cultures, and many elements of these holidays are still celebrated on May 1 today, such as the Maypole. "May Day" also refers to various socialist and labor movement celebrations conducted on May 1, unrelated to the traditional celebrations to commemorate the Haymarket Riot of 1886 and the international socialist movement generally. The latter event is an important holiday in Communist countries and Waldorf Schools.
In America, May Day is commonly celebrated as a commemoration of the Haymarket Riot of 1886 in Chicago, Illinois, which occurred on May 4 but was the culmination of labor unrest which began on May 1. The date consequently became established as an anarchist and socialist holiday during the 20th century, and in these circles, it is often known as International Workers' Day or Labour Day. In this form, May Day has become an international celebration of the social and economic achievements of the working class and labor movement.
The earliest May Day celebrations appeared in pre-Christian Europe, as in the Celtic celebration of Beltane, and the Walpurgis Night of the Germanic countries. Although the pagan-oriented celebrations faded as Europe became Christianized, a more secular version of the holiday continued to be observed in the schools and churches of Europe well into the 20th century. In this form, May Day may be best known for its tradition of dancing the Maypole and crowning of the Queen of the May. Today many Neopagans, especially Wiccans, celebrate reconstructed versions of the old pagan holidays on May 1.
Regards,
Pravin P.