Unexpected results in Multisim
There is probably an issue with your 2N7002 SPICE model. Here are results from three different SPICE models (5V Vds, +4V or -1V gate voltge). 

          ON             OFF


Philips:      201mA          19pA

Fairchild:    385mA          600nA

Zetex:        206mA          833nA 

Needless to say, the OFF currents are hardly trustworthy, but it does behave more-or-less as you'd expect. Here's the Philips model for your comparison: *---------------------------------------------------------------------------
*
.SUBCKT 2N7002/PLP 1 2 3
Cgs  2 3 12.3E-12
Cgd1 2 4 27.4E-12
Cgd2 1 4 6E-12
M1 1 2 3 3 MOST1
M2 4 2 1 3 MOST2
D1 3 1 Dbody
.MODEL MOST1 NMOS(Level=3 Kp=20.78u W=9.7m L=2u Rs=20m Vto=2 Rd=1.186)
.MODEL MOST2 NMOS(VTO=-4.73 Kp=20.78u W=9.7m L=2u Rs=20m)
.MODEL Dbody D(Is=125f N=1.023 Rs=1.281 Ikf=18.01 Cjo=46.3p M=.3423
+            Vj=.4519 Bv=60 Ibv=10u Tt=161.6n)
.ENDS
*
*---------------------------------------------------------------------------
*