Can't plot with GNUPlot

[Bo Yang]

Hi,
   My Octave version is 3.0.5, and my gnupot version is 4.2 patch level 5, when I try to plot:

 A=[1,2,3]
 B=[4,5,6]
 plot(A,B)

I got following errors:
octave:8> plot(A,B)

gnuplot> plot "-" using ($1):($2) axes x1y1 title "" with lines linestyle 1 ;
              ^
         line 0: use 'set term' to set terminal type first


gnuplot> 1 4
         ^
         line 0: invalid command


gnuplot> 2 5
         ^
         line 0: invalid command


gnuplot> 3 6
         ^
         line 0: invalid command


gnuplot> e
         ^
         line 0: invalid command



I can't find the answer through Google, please help me, thanks!

Regards!
Bo