TFile *f = TFile::Open("root://glast-rdr//wilko/test/basic.root")
will load TXnetFile automatically
root[2 ] .L lib/libNetx.so
root[3] TFile *f = new TXNetFile("root://glast-rdr//wilko/test/basic.root"))
requires that the library (Netx.so) that contains TXNetFile has to be loaded first.