When word-wrapping text, the wordwrap function fails to reset its character count when encountering the break character in input text.  As an example, when supplied with the text 

"foo bar\n<70 characters here> baz"

it will break before 'baz', instead of some time after 'baz' as it should (assuming the standard 75 char line length and \n break char)

I've checked the source ( /ext/standard/string.c roughly around lines 395, 405, 442 and 456) and this is indeed the case.  I can probably find time to write and send a patch to the appropriate person if necessary, but this may be more hassle to integrate than that person just doing the easy fix themselves :-)