Thanks for your reply,
sorry if I misunderstood, but my datetime web part isn't in a scrolling text web part...
I've just added the webpart in the "design" tab, in a page that has no scrolling text web part.

I've tried to insert the DateTime web part in different pages (with and without some "MainContent")... but in every case, i never get the date displayed.

How should i proceed to make it works through the portal engine? (instead of "Timer" result).

Thanks