casting problem

I modified the SPI OVM testbench that can be downloaded from Mentor's web site.  The testbench is customized to test our design.  I have been using Mentor's Questa tool to run simulation while we evaluate the tool.  The testbench has worked with Questa.  We are also evaluating Cadence's Incisive.  I started to compile and run simulation with Incisive.  It apprears to compile OK but $cast does not seem to work right.

    seq_item_port.get_next_item(req);
    $cast(cloned_item, req.clone());
    ap.write(cloned_item);

This works fine with Questa but not with Incisive.  The data members in req are defined but not cloned_item after $cast.

Is there any reason that this does not work with Incisive?  Questa was sourceing OVM-2.1.2 source code.

Thank you!