Redmine

Ir probably is, the source is open after all, but you'll have to dive into the code :-)

yep, spent last night trying to dive in the redmine sources (i'm a newbie)

i found that redmine is using some kind of "textile" and it's inside /lib/redmine.

there are a few files but it seems that it is the code of the whole tag parser, not the tags themselves. i and couldn't find their definitions anywhere :(

could anyone more experienced give any hint where should i look?

Do you want to just add a button for a custom javascript, or add a custom tag for something?

i would like to add a button for custom tag

like, i don't know, [test]content[/test] would wrap content into <span style="font-weight:bold;font-size:0.5em;">(for example)</span>

Well you would need both of them then, but extending textile with more tags won't be easy, and you have been looking at the right spot for that. There is no easy "drop-in" way to extend the markup language I know of, sorry.