John, I ran the Gspot program is says that the codec is
S-mpeg 4 version 2
and that the codec is installed.
The files do import and playback on the timeline, but crashes when using media encoder
Same here. I have investigated it and realized this is not problem of CS5, but serious problem of AME. It crashes during initial phase of encoding ("conforming media"). Adobe should fix it asap, we are not only one who already met this problem.
Wi7 X64 Ent.
Intel Xeon E5504 (SSE2 for sure)
Have you applied the Adobe Media Encoder CS5 (5.0.1) and Premiere Pro CS5 (5.0.2) updates?
If the problem persists after you've installed the update, please file a bug report.
I did, right before my first post. No change...
I have tested it also on my laptop with Intel Core2 Duo, Win7 x64 - same issue.
It seems to me AMEs codecs are not correctly optimalized for x64 architecture...