Me thinks you need 3 days to settle and get the money into your account....however, you are 'locked' into whatever price you sold at immediately.....
example : I think you can sell stock on the 31st and still use for tax purposes, as the revenue/loss is derived from a sale dated in 2008.....even if, after 3 day settlement period it could be Jan/2009 before your funds are cleared.....
I owe to smoking (cigars), more or less,
Through life the whole of my success;
With my cigar I'm sage and wise -
Without, I'm dull as cloudy skies !
Light up a stogie today !!