[OS X TeX] Medium long heading

[Alain Schremmer]

While I am at it: Companion 2ed deals extensively with "very long  
headings" but not with a heading that is just a bit too long so that  
it could encroach just a little bit in the right margin. But I don't  
know how to prevent the break.

Specifically,

Here is what I would like:

Exceptional Rational Functions:
Degree = 0	

Exceptional Rational Functions:
Degree = 1	

Here is what I am getting:

Exceptional Rational
Functions:
Degree = 0

Exceptional Rational
Functions:
Degree = 1

Hopeful regards
--schremmer