I need to get the adapter from the form, but still could not.
In my controller I can recover the adapter using the following:
The other various answers here generally correct, for ZF < 2.1.
Once 2.1 is out, the framework has a pretty nice solution. This more or less formalizes DrBeza's solution, ie: using an initializer, and then moving any form-bootstrapping into an init() method that is called after all dependencies have been initialized.
I've been playing with the development branch, it it works quite well.