[texhax] specific look for theorems etc.

[Florian Knorn]

hello !

this is my first message to this mailing list. i am uncertain if it is 
okay to ask a LaTeX-related question, but please bear with me.

i recently saw a very nice way of formatting theorems etc. in a book and 
i'd like to use that for my thesis. it looked like this:

Definition 6 (Some Name) _____________________

Some text texttexttexttext text text text text
.
.
.
finishing. ___________________________________

the thing i'm interested in is the hrulefill (?) in the title and at the 
end. how can i produce this in an automated way ? i use the ntheorem 
package (for a couple of other reasons), but i didn't manage to make it 
behave like this. i tried using \theoremseparator{\hrulefill} and 
\theoremsymbol{\hrulefill}, but that doesnt work : ( any ideas ?

thanks for your help and greetings from ireland,

florian