A quick search in the JMP DOE documentation
Help==>Books==>Design of Experiments Guide
the following quote was found
"Tip: In the Fit Model window, JMP Pro users can change the Personality to Mixed Model."
and from the Fitting Linear Models book
Help==>Books==>Fitting Linear Models
"Note: JMP Pro users are encouraged to use the Mixed Model personality in the Fit Model
window. The Mixed Model personality offers a broader set of covariance structures than does
Standard Least Squares."
So it appears the answer to your question is, Only in JMP Pro
Jim