We just release Flash Media Server 3.5.2 on Adobe.com (see link below)
This service pack release is a bug fix release focusing of improving transitions for Dynamic Streaming content, more support for multibitrate live encoders plus increasing memory management under heavy load. We’ve also added a few more event messages to help developers respond when exceptions happen. This release also addresses a security issue around remote procedure calls (we also back ported that fix in version 3.0.4).
DOWNLOAD FMS 3.5.2 today: http://www.adobe.com/support/flashmediaserver/downloads_updaters.html