[pmwiki-users] Recent Changes shows "by ?:"

[JamesM]

Hi,

I've jst discovered PMWiki and i realaly like it so far. I am implementing 
it to use as a Team resource and troubleshooting repository.

However, i notice that when i click the "Recent Changes" link, it does not 
show a username for who edited the page, only a "?". 

Example:
Projects . . . July 26, 2013, at 07:24 PM by ?: 

How do i configure the wiki to show this information?

Thanks. JamesM