Devonagent doesn't like me

Devonagent doesn't want to work for me. It does not make any sense... doesn't work at home with the Powerbook - ok, I am behind APX, but it doesn't work at work either - behind an interesting firewall. It can not be nor APX since Sergio has it running behind APX and linksys, and I saw people at work test it under similar network / firewall settings. So at work it does not run neither on the G5 nor on the eMac. All with the same error - does not find any data.
It can't be even using a weird port, since otehr people with same settings and from same location get it work. I don't get it.