Javascript, jquery or what the hell…

Hello Guys,
I hope I’m on a right place.
I’m using a designer plugin which doesn’t wanna work properly. I “spoke with the developer, on them side its working fine.
Now i find some mistake message in FF Console: “TypeError: $d is not a function”
I know its not sooo much, but any idea where can be the problem?
Plugin, hosting or my coputer from the museum?

Thanks for any idea.
Zoltan