How do I fix this calendar javascript code?

Answer 1

After retrying the code after noticing the comment about May being wrong, here's some code that seems to work much better:

replace this block of code (from the original javascript code):

startspaces = thisdate;
while (startspaces > 7) {
    startspaces -= 7;
    startspaces = thisday - startspaces + 1;
}
if (startspaces < 0) {
    startspaces += 7;
}

with this single line of code:

startspaces = thisday;

Note that I use thisday and not thisdate here.

This seems to work for all of 2009.

Answer 2

Solved the problem found a control as you said, never using this script again.

Answer 3

This javascript-calendar is very nice, easy to customize and no server-callbacks: http://www.codeproject.com/KB/scripting/DropCalendar.aspx