Probelms simulating Xilinx FFT version 3.2 core in ModelSim SE

Hello,

I am using Xilinx 9.1i and Modelsim 5.7g. I instantiated a coregen module for FFT ver 3.2. After successfully synthesizing the module with the generated xco, I am now trying to simulate the module. The hierarchy is as follows: fft_tb => fft_top => fft.v (generated by coregen)

I am using a custom script as follows: ############################################# vlib work vlog fft.v "../fft_top.v" fft_tb.v vsim -t 1ps -L xilinxcorelib_ver -L unisims_ver -L simprims_ver -lib work fft_tb_v glbl view wave add wave * add wave /glbl/GSR do {fft_tb_v.udo} view structure view signals run 1000ns ############################################## I have compiled simprims, xilinxcorelib and unisim libraries (verilog versions) and added them to Modelsim. When I select Simulate Behavioral Model from Xilinx, it opens modelsim and finds all the xilinx primitives, which fft module calls, except for these:

# ** Error: (vsim-3033) fft.v(10097): Instantiation of 'fft_r22_cnt_ctrl_6' failed. The design unit was not found. # Region: /fft_tb_v/uut/U1 # Searched libraries: # C:/Xilinx91i/verilog/mti_se/XilinxCoreLib_ver # C:/Xilinx91i/verilog/mti_se/unisims_ver # C:/Xilinx91i/verilog/mti_se/simprims_ver # work # ** Error: (vsim-3033) fft.v(10111): Instantiation of 'fft_r22_cnt_ctrl_7' failed. The design unit was not found. # Region: /fft_tb_v/uut/U1 # Searched libraries: # C:/Xilinx91i/verilog/mti_se/XilinxCoreLib_ver # C:/Xilinx91i/verilog/mti_se/unisims_ver # C:/Xilinx91i/verilog/mti_se/simprims_ver # work # ** Error: (vsim-3033) fft.v(10183): Instantiation of 'fft_r22_cnt_ctrl_8' failed. The design unit was not found. # Region: /fft_tb_v/uut/U1 # Searched libraries: # C:/Xilinx91i/verilog/mti_se/XilinxCoreLib_ver # C:/Xilinx91i/verilog/mti_se/unisims_ver # C:/Xilinx91i/verilog/mti_se/simprims_ver # work

So I dont understand why these primitives are present in the core and why are they not subdivided into modules which are present in simprims library or any xilinx library for that matter.

Is it a problem of using older Modelsim version with new xilinx version? Do I need to upgrade ips for 9.1, I am currently working with the ip set provided in xilinx installation?

Any ideas how I can fix the problem?

Thanks in advance

Mansoor