noise analysis using ngspice on fedora10 machine

[sandhya save]

i am faing problem while running noise analysis in ngspice
the netlist is like this
vin1 101 0 ac 1
vin2 100 0 ac 0

..
.ac dec 10 1 10000e6
.noise v(6,0) vin1 dec 20 10 10000e6
.print noise v(6,0)
.probe
.op
.end

# ngspice -b opamp.spice> opamp.out
Warning : can'nt parse '6' : ignored
Warning : can'nt parse '0' : ignored
Error: no data saved for Noise analysis; analysis not run
doAnalyses: not found
run simulation(s) aborted
Error:.print: no noise analysis found

can anyone help in this matter?