XSS vulnerability in Mojo Mail Sign-Up Form

[Daniel Boland <Electrophreak () blueyonder co uk>]

Heya, this is my first post here so go easy on me plz. I posted about this 
on the Mojo Bug Tracker ages ago and it's just been ignored, and besides, 
Im losing faith in reporting to the vendor, PHP Arena took the credit for 
an XSS bug I found in their paFileDB. But anyway, Mojo Mail doesn't filter 
sign-up requests, here's an example on Mojo's site:

http://mojo.skazat.com/cgi-bin/mojo/mojo.cgi?flavor=subscribe&email=%
3Cscript%3Ealert%28%22XSS%20Vuln.%22%29%3C%2Fscript%
3E&list=skazat_design_newsletter&submit=Submit

I don't know if I'm supposed to say more but it's just XSS, I think that's 
it?
~ElectroPhreak