function daysInMonth(m,y) {
if (m==1) //feb
if ((y%4 != 0) || (y%100 == 0 && y%400 != 0)) return 28
else return 29
else //other months
return [31,0,31,30,31,30,31,31,30,31,30,31][m]
}

function addCalendar(){
//table header
//text='<table style="font-size:10px"><tr><td>Пн</td><td>Вт</td><td>Ср</td><td>Чт</td><td>Пт</td><td>Сб</td><td>Вс</td></tr><tr>'
text='<table style="font-size:10px"><tr><td>Вс</td><td>Пн</td><td>Вт</td><td>Ср</td><td>Чт</td><td>Пт</td><td>Сб</td></tr><tr>'
//get 1st date's day of week
day=new Date()
today=day.getDate()
month=day.getMonth()
year=day.getFullYear()
day.setDate(1)
day=day.getDay()
//day=(day)?day-1:6 //fix to russian notation
//fill the emptiness before
for(col=0;col<day;col++)
text+='<td> </td>'
//col=day
//fill the main structure
last=daysInMonth(month,year)
for(day=1;day<=last;day++){
style=''
//if(col==5)style+='color:blue;'
//if(col==6)style+='color:red;'
if(col==0)style+='color:red;'
if(col==3)style+='color:blue;'
if(col==6)style+='color:blue;'
if(day==today)style+='border:dotted thin;'
text+='<td style="'+style+'">'
text+=String(day)
text+='</td>'
if((col==6)&day!=last){
col=0
text+='</tr><tr>'
}
else col++
}
//fill the emptiness after
for(;col<6;col++)
text+='<td> </td>'
text+='</tr></table>'
s=document.getElementById('sideBar')
d=document.createElement('span')
a=document.createElement('a')
a.innerHTML=text
a.href='http://vkontakte.ru/events.php?act=calendar'
d.appendChild(a)
s.appendChild(d)
}

document.addEventListener("DOMContentLoaded", addCalendar, false);