Well its not setup to do so. Its quite an involved change but if you wanted to change the forum module to use html you would need to do a couple of things

* Change the Post 'Content' field to be an HTMLField
* Remove all the BBCode parser calls
* Change the Post form to use a 'HTMLEditorField' instead of a 'TextField'

There is probably more steps (you probably need to create a custom HTMLEditorConfig setting as well since you don't want the full CMS html editor in the front end)

There is an open ticket for this work too - you may want to add yourself as a cc on that so you can be alerted of any progress. http://open.silverstripe.org/ticket/4867.

I am currently scoping what features forum 0.3 will have but I doubt this will be one of them. The main thing I am worried about is for everyone that likes the WSYIWYG there will be one that doesn't and wants bbcode. Some people will want Html But NOT in tinymce (like wordpress.org). Its a matter of providing a solution which works for the wide range of people using the module.

Thanks SecretSquirrel it is on the list for Forum 1.0 which is not due for a while. If you require the feature for a project you could potentially hire a developer to do for you.

If anyone wants to contribute this feature I would be more than happy to help answer questions and help get it into the module.

AFAIK it stores the content as plain text in the backend (with bbcode tags) then parsed at read time. Internally we probably want to change that so it stores it as HTML in the database since that's the only common denominator between any languages. Though storing it as HTML you would then need to make BBCode work 2 ways (to support edit forms it needs to convert html back to bbcode) which at the moment I don't think it has?

The parsing on the front end could be mitigated via partial caching which will be a good enhancement for the forum.