Fortunately I have a bluetooth enabled Sony Ericsson T630, that pairs quite well with bookah's builtin bluetooth. I can use this feature out of the box -> O'Reilly Network: Use Bluetooth for SMS.
Also, using the phone as a temporary dialup modem worked like a charm. Although since GPRS is just ridiculously expensive, I need to refresh my ultra rusty ipfw skills to filter just the right traffic for a given task (e.g. Only allow ssh traffic for emergency server interventions). I haven't found yet an email client that allows partial downloading of emails. Like, say limit the size to 5kb per email, or just download the email subject. So email via GPRS is a big no-no on bookah, unless of course I want my wallet to scream.
Good news! To support my GSM modem addiction, the kind folks at itegno emailed me a copy of their Mac OS X drivers. Next step is to find a javacomm API implementation for the Mac. Which inspite of its FreeBSD lineage (Mac OS X uses FreeBSD for its userland implementation), doesn't support the javacomm API out of the box.