parfor and se_randomizeseeds error

I'm having trouble randomizing my GlobalSeed for a SimuLink model inside parfor with 8 workers. The same code works flawlessly if I remove the 'par' from the 'parfor'.

Code

    parfor r = 1:testing_depth
      %code
      %
      %
      for i = 1:iterations
        seed = mod(floor((i/iterations) * now * 8640000),2^31-1);
        se_randomizeseeds(modelname, 'GlobalSeed', seed);
        sim(modelname);
        %code
        %
        %
      end
    end

Output (command window)

    Starting parallel pool (parpool) using the 'local' profile ... connected to 8 workers.
    Depth test: 4/10 (1000 iterations per depth)
    Depth test: 7/10 (1000 iterations per depth)
    Iterations: 
    Iterations: 
    Error using cpf_v5 (line 58)
    Invalid block or system specified. Type 'se_randomizeseeds' for more information.

    >> se_randomizeseeds
    Error using se_randomizeseeds (line 37)
    Missing block(s) or system(s) as first input argument. Type 'help se_randomizeseeds' for more information.

    >>

[Edric Ellis]

I don't know much about se_randomizeseeds - but does it help to say

load_system(modelname)

before you do that?