I'm using two plugins, Magic fields (1.2.1) and Custom fields taxonomies(1.4.1b).
There seem to be some problem with these two. For example, I have a custom field called 'age' which I have also registred in CFT.
When I have both plugins activated I get a blank page when trying http://mysite.com/?age=12
If I deactivate Magic fields I works ok.
I has been working before but when I updated the plugins, it stopped working. Not sure if this relates to CFT or MF. I will also post this in their forum.
Cheers,
Jens
http://wordpress.org/extend/plugins/custom-field-taxonomies/