The easiest way would probably be to grab the DOM tree after MarkupParser.parse(), and do a series of simple translations. For example, through a custom WikiRenderer. Storing of the Mementos would need to be done in the HttpSession.

From ChangeLog for JSPWiki 2.5.7

Added CreoleMarkupRenderer, which currently supports WikiCreole 0.2 syntax. This is a highly experimental feature. You can't do much with it yet, since we're missing a backconverter.

Known Problems

• links including tilde (~) or colon (:) get cut off after these characters
• images within nowiki render strangely
• no escape character support yet

Same syntax with Creole 0.3

Lists, Horizontal Rule, Preformatted, Tables

Differences between JSPWiki and Creole 0.3

Bold

 __bold__ 

 **bold** 

Italics

 ''italics'' 

 //italics// 

Headers

!!!Large
!!Medium
!Small

====== Small ======
===== Small =====
==== Small ====
=== Medium ===
== Large ==
= Large =

Links

[Google|http://www.google.com/]
[This is a page|Page]

[[http://www.google.com/|Google]]
[[Page|This is a page]]

Images

[{Image src = 'myimage.jpg'  caption = 'this is my image'}]

{{myimage.png|this is my image}}