A while back, I updated how forward- and backward-paragraph work in 
Eshell so that we didn't have to rely on regexps to detect the prompt 
(paragraph navigation in Eshell has always stopped at prompts as well as 
blank lines separating paragraphs). I got that implementation wrong, and 
since then it's only navigated between prompts. Attached is a patch to 
restore the proper behavior, plus some tests to make sure I got it right 
this time.