It appears that Word 2010 will not take the opportunity to hyphenate a word following a typed hyphen. For example, I would like the word "post-processor" to be split to a new line following "post-" if there is insufficient space on the line. If I use an optional hyphen then the word splits as expected, but then I don't get the hyphen when the word fits on a line.
Interestingly (well at least for me), the word "processor-post" does get hyphenated following "pro" and "proces", but not unfortunately at the hyphen.
Hopefully there is a setting or version that will solve this problem.
My Word 2010 does work "correctly", as you expect, without any additional intervention. Just type the normal hyphen between the 2 words, they wrap at the hyphen when the words approach the margin of the page. I have to be in "print layout" view. Actually I can't defeat it. Even in Web view it works correctly. The only thing I can think of is that you are not using a hyphen character, but some other character that looks like one.