CMS Made Simple Forums

I can't seem to find this anywhere (Google, documentation), but is it possible to create a date-field in a template, sort of in the same way you'd add a date to a newspost?

Not by default it is, but you might investigate this post. http://forum.cmsmadesimple.org/index.ph ... .html 
I don't know what the current status is there, so better read all the pages