[Mediawiki-l] what is wrong in "<math>z</math>"?

[Massimo Canonico]

Hi,
I'm quite confuse about this error. If you go in this link:
http://dcs.di.unipmn.it/wiki/index.php/Param-sim#BoT_Size

you can see the error:*
"Failed to parse (PNG conversion failed; *

*check for correct installation of latex, dvips, gs, and convert): z*"

What is surprise me most is that, if I change it to
<math>Median</math> at it was before, I do not get any error.

Do you have any idea about this?

Today, I have just restarted apache since I have changenged the "max 
upload file size" and I have added "pdf" as one of the possible file 
extensions.

Thanks,
  Massimo