Problem with ON UPDATE CURRENT_TIMESTAMP

[SamBones]

It's supposed to be possible to put a "[tt]DEFAULT CURRENT_TIMESTAMP[/tt]" and/or "[tt]ON UPDATE CURRENT_TIMESTAMP[/tt]" clause on a [tt]TIMESTAMP[/tt] or [tt]DATETIME[/tt] column when creating a table. I'm getting an error on the "[tt]ON UPDATE[/tt]". Is this not possible with MS SQL Server?

CREATE TABLE testTbl (
	id		INT,
	txt		VARCHAR(100),
	ts		TIMESTAMP	DEFAULT CURRENT_TIMESTAMP ON UPDATE CURRENT_TIMESTAMP
	);

Msg 156, Level 15, State 1, Line 9
Incorrect syntax near the keyword 'ON'.

I'm an Oracle guy adrift in a SQL Server world.