with Visual boy Advance in the FAQ's he had listed something like
Q: Is it possible to play GBA Games over the internet?
A: No it is not.
You would need a constant connection of 2mbps in order for it to work properly.
I don't remember EXACTLY what it said and the site has been down for awhile now.
so unless someone was able to add kaillera to VBA or somehow get it to work with it your kind of out of luck for now but keep hope it should appear sooner or later, it always does.