If you are building SWF10 content and discovered that your SWFs are no longer working with the refresh of Flash Player 10 beta that went live on Adobe Labs last week, you will need to download the latest compiler from the Adobe Open Source site. Build 3.1.0.2148 available on the FlexSDK open source site contains the compiler you will need to do the re-compile.

The reason why the re-compile is necessary is that we are making a change in how we differentiate the APIs for one version of Flash from another. Previously we used namespaces to make that distinction, but we are changing to a system based on metadata. It isn’t something that developers need to be concerned with, I just wanted to provide some insight.

Keep in mind as you do your re-compile that this is a beta, and some of the APIs have changed since the first beta post of Player on labs. A new version of the documentation also was posted last week, so make sure to download that as well.

Also note: There may be a prob or two doing Export Release in Builder with build 3.1.0.2148. the Flex team is looking into it and if needed will make updates in later SDK builds.