Flash: start playing before the whole file is downloaded

Hi, I'm using JWPlayer 5.10. When using the FLASH player, playback won't even start until the WHOLE FILE is downloaded. How do I avoid that? Note that I'm NOT talking about being able to skip to not-yet-downloaded parts of the video (what some call pseudo-streaming). I do know that Flash can only download the whole file from beginning to end. I know partial-content-based http streaming is possible only in HTML5 mode and I know that a pseudostreaming workaround is possible in flash but requires additional modules on the server to supports it. I don't care about that. Even though downloading the file from beginning to end, Flash is supposed to be able to start playing when a sufficient portion of the file has been buffered, while it keeps downloading the rest. Also, you should even be able to skip ahead within the part of the video that has already been downloaded (not any further than that). However, that's not happening. It only starts playing when the whole file is downloaded. I'm testing with a video file which is about 1 and a half minute and 9MB. By using Chrome's Developer Tools I can verify that the whole 9 MB are really downloaded (which takes about a dozen of seconds) before it starts playing. I'm confused: that should work out-of-the-box. What am I missing? Thanks in advance.