gSpice: 'model is not a mosfet' error message
I don't know gSpice specifically, but in ngSpice (a SPICE3-based free SPICE), the syntax for a MOSFET card is 


  MXXXXXXX nd ng ns nb mname ...


Notice, four terminals must be specified: drain, gate, source, and body.

In your deck you specified only three connections, and the simulator probably thought DMP2004WK was the name of a new node where the body is connected. 

Typically the body of a PMOS should be connected to the source or to a positive voltage rail.