Adaptive fill question

[Richard Bourgon]

Quick question: 

In text mode with autofill on, if I start a paragraph like this...

   1. Blah blah blah blah.

...and get to the fill column, it wraps around and starts a new line: 

   1. Blah blah blah blah. The text
   1. gets wrapped like this. Annoying!

How can I stop this behavior and instead get Emacs to (i) indent under the 
"Blah" but (ii) prepend spaces rather than "1. "?

adaptive-fill-regexp is set to

    [   ]*(?[0-9]+[.)][         ]*

and adaptive-fill-first-line-regexp is currently empty. (The square braces 
contain a space and a tab.)

Thanks in advance,

Richard