Modelsim simulation of Quartus primitives

I am attempting to simulate a design which includes the LATCH primitive (in this case, to capture data from the DE1 external SRAM for a read operation). It compiles in Quartus2, and I load it up in my testbench in Modelsim Altera Starter edition, but the latches don't seem to function.

It seems that the "iq" internal signal correctly follows the "D" input, but Modelsim doesn't appear to be executing the Q <= IQ statement following the process, and the latch effectively never latches anything.

Is there something I'm failing to configure properly here? Thanks in advance for any help.

Using Modelsim ASE 6.5b and Quartus2 10.1sp1.