From the CS5 user guide PDF
Stream for best performance
You can stream FLV and F4V files to eliminate download time. FLV and F4V files also have deep interactivity and navigation capabilities when they are streamed. Streaming FLV and F4V files allow you to monitor quality of service. You can stream FLV and F4V files with the Flash Media Server. Alternatively, you can use a hosted service from one of the FLV/F4V Streaming Service partners available through the Adobe website. For more information, see "Delivering Flash Video: Understanding the Difference Between Progressive Download and Streaming Video" on the Flash Developer Center website.
Thanks John for your answer. Unfourtunatly I need to use the H.264 and MP4, not flv or f4v. FLV and F4V is not supported by some mobile devicees, as I understand it.
I'm not recommending anything.. but just for your reference add this link...
there is a lot on internet about code to use for HTML5 in order to detect browser or device, and then deliver the format for streaming that device or browser needs...
this stuff changes so fast its very difficult to keep up with those changes, which is why a lot of people use places like youtube and vimeo etc..
Have you tried the presets found under H.264 in the Export Settings?
Many export settings for the web, phone and tablet.
Yes - I can not make the seeking work with those presets - there must be some setting whitin the setting that makes it possible to seek in the video (click on timeline and make the stream go to this point right away, even if it has not been streamed so far yet in play back - I think the english term for this is seek (?) )