[the-economist]

Issue: Connected 9900 to mac and enabled wireless media sync. It did its thing and presented the itunes library when finished. A sync for good measure and eject.
Wireless sync is now present on BB but refuses to connect although on same LAN with mac.

A bit of debugging shows a server binded and listening on port 4481, although i wasn't bored enough to dump the traffic we suspect a control channel on 4481 for negotiations and 4482 used for the actual transfers. Official Blackberry documentation suggests both of them to be open but gives no further info.
I dumped the socket list though and saw the daemon listening and even a connection with the BB was established. No traffic though and no library visible on BB.

Solution: Encryption was enabled on the BB and included the SD card + media. This needs to be disabled for the actual transfer to go through. (I enabled it back again when finished and everything still works).

If you've already passed the initial installation of Wireless Sync and after disabling encryption you want to start fresh the config files are stored in a hidden folder under the Blackberry folder in the SD card called System.
Deleting the configs from there (which are appropriately named) and disabling/re-enabling Wireless Sync from DM would trigger a fresh install.

Have fun