Hi,
the current release is not completely compatible with blackberry devices.
we've added such compatibility for our next release.
You can check a preview of such release here:
http://www.lightstreamer.com/whatsNew.htm#2011/02/lightstreamer-40-preview-release.html
The new version of the sdk also contains a blackberry example. Check it out as it shows how you'll need to use the library to work with blackberry devices.
let us know if you have any issue.
HTH