DOCBOOK-APPS: Callout formatting

Hi,

I'm new to docbook and xsl so if these are daft questions I'm sorry. 
 Firstly, how can we get square brackets instead of round brackets in 
textual callouts using the XSL sheets?


e.g.

A portable[1] program...

...

[1] both in terms of compiler and platform!



Secondly, how do get call outs to be displayed inline in html output? 
 e.g. the output is something like this (it looks like superscript)

(1)
   both interms of compiler and platform

but I'd like it to look like


(1) both interms of compiler and platform

how can this be done using xsl?


Is this even the right mechanism for what I'm doing? (don't actually 
know the name of those little numbered things you see in books, took me 
ages to find callouts).


Regards,
Chris Campbell