Hi, I am trying to implement application using qt dbus module, Which will call SetProperty with parameters QString, QVariant. using dbus-send i am using the following command... sudo dbus-send --system --type=method_call --print-reply --dest=org.ofono /phonesim0 org.ofono.Modem.SetProperty string:"Powered" variant:boolean:true In the above command, According to my knowledge, I interpreted the things as below... Type of bus : systembus Type of call : method call service name : org.ofono object path : /phonesim0 Interface name : org.ofono.Modem method name : SetProperty which means ( "sv" -- string, variant) I am trying the same thing using qt program... QDBusConnection bus = QDBusConnection::systemBus(); QDBusInterface dbus_iface("org.ofono", "/phonesim0/operator/23402", "org.ofono.Modem", bus); bool value = true; dbus_iface.call("SetProperty", QString("Powered"), QVariant(QVariant::Bool, &value)); I am getting output as below o/p.. QDBusMessage(type=Error, service="", error name="org.freedesktop.DBus.Error.UnknownMethod", error message="Method "SetProperty" with signature "sb" on interface "org.ofono.Modem" doesn't exist ", signature="", contents=([]) ) Please find that "sb" which is analysed as "string and boolean" parameters. Can any one suggest what is wrong with is piece of code... regards,KK. _________________________________________________________________ South Cinema This Decade http://entertainment.in.msn.com/southcinemathisdecade/