I beleive that you can add multiple buddies, and then commit the list. Other than that I would setup a que of buddies to add, add one, and then add another and commit everytime you get the buddylist_ok() or buddylist_error().

Calling do_one_loop manualy between each call will be iffy at best. Its going to go check each socket and see if there is something new. If there is no message then it returns, if there is then it processes it and calls the event. You would be counting on your events to come at the right time and in the right order, which is generaly a bad idea. I think you should probably focus more on how to fit your needs into an event driven program.