This is beyond cool! Idokorro (makers of two other very cool products Mobile Admin and Mobile Desktop) have just launched the first public Citrix Client for the Blackberry platform. One could argue that a Citrix client on a Blackberry is not the ideal platform for getting work done, but I've been using it as I used the Mobile Desktop product - for on the go deperate troubleshooting (i.e. I don't have a laptop near me, but need to get in a reboot a system, etc). Anyway, checkout their website for a download link (they even have an OTA download available from mobile.idokorro.com
On one of my Presentation Server 4.0 boxes, I'm receiving the typical TS error message that you're not a member of the Remote Desktop Users group. This is weird since this system works perfectly fine locally as well as via WI/CSG. I've exchange emailed with the Idokorro folks who mentioned that they've seen this on about 4-5% of the downloaded installs. They are currently researching a fix and expect it to take no longer than 1-2 weeks (how's that for support!).
UPDATE: Idokorro has released a beta client that fixes the TS error message. Contact them down a download URL.
Anyway, one of the REALLY cool things about this product is that it supports either connecting directly via TCP/IP through your carrier (for externally facing Citrix connections) or more appropriately you can tunnel through your existing BES/MDS service (which is awesome if you're trying to fix a problem with your WI/CSG config). I just can't speak enough about how cool this product is.
Pricing is $35 per device (which IMHO is pretty reasonable). Of course volume discounts would bring that price down.
Checkout their press release here
Enjoy!
Shawn