[Users] PA module doesn't work

Hello, I'm using Openser 1.0.1 with PA module and eyebeam clients. When eyebeam receives a presence NOTIFY to a SUBSCRIBE, it responds with a "481 Call/Transaction Does Not Exist". Why? I've read that PA is unstable, but I suspect that this module doesn't work properly. This is a piece of the cfg file: loadmodule "mysql.so" loadmodule "sl.so" loadmodule "tm.so" loadmodule "rr.so" loadmodule "maxfwd.so" loadmodule "usrloc.so" loadmodule "registrar.so" loadmodule "textops.so" loadmodule "avpops.so" loadmodule "uri.so" loadmodule "jabber.so" loadmodule "pa.so" loadmodule "auth.so" loadmodule "xlog.so" ... modparam("pa","use_db",0) ... route{ ... if (method=="SUBSCRIBE") { if (t_newtran()) { handle_subscription("registrar"); }; return; }; if (method=="PUBLISH") { if (t_newtran()) { xlog("L_ERR", ">>>>>>>>>>>>>>> PUBLISH REGISTRAR SIP"); handle_publish("registrar"); }; return; }; ... }