Problematic RTMP Server - Tinychat [[DYNAMIC]]?

[rtmpdumpuser]

I was previously able to download streams from tinychat.com using rtmpdump, but they recently made some adjustments to their server and now I cannot.

Here are typical headers flash sends to tinychat's rtmp server:

rtmp://174.122.202.2:80/tinyconf/5010
app: tinyconf
flashVer: WIN 11,0,1,152
pageUrl: http://tinychat.com/testroom
swfUrl: http://tinychat.com/embed/Tinychat-1...on=1.0.0.0301/[[DYNAMIC]]/8
tcUrl: rtmp://174.122.202.2:80/tinyconf
playPath: 5010

From this I invoked rtmpdump with the following arguments

rtmpdump -r "rtmp://174.122.202.2:80/tinyconf/5010" --app tinyconf --flashVer "WIN 11,0,1,152" --pageUrl "http://tinychat.com/testroom" --swfUrl "http://tinychat.com/embed/Tinychat-10.3-1.0.0.0301.swf?version=1.0.0.0301/[[DYNAMIC]]/8" --tcUrl "rtmp://174.122.202.2:80/tinyconf" --playpath "5010" -W "http://tinychat.com/embed/Tinychat-10.3-1.0.0.0301.swf?version=1.0.0.0301/[[DYNAMIC]]/8"

but rtmpdump fails with

WARNING: HandShake: client signature does not match!
INFO: Connected...
ERROR: Closing connection: NetStream.Play.Failed

There are also some additional headers which I cannot replicate using rtmpdump:

DEBUG: Property: <Name:     objectEncoding, NUMBER:     0.00>
DEBUG: (object end)
DEBUG: Property: <Name:           no-name., STRING:     testroom>
DEBUG: Property: <Name:           no-name., STRING:     none>
DEBUG: Property: <Name:           no-name., STRING:     default>
DEBUG: Property: <Name:           no-name., STRING:     tinychat>
DEBUG: Property: <Name:           no-name., STRING:     >

Is anyone able to download tinychat streams through rtmpdump? I think the problem may be related to the [[DYNAMIC]]. What could [[DYNAMIC]] represent/mean?