In the "Clock Buffers" window, if I select "Local Routing" in the "Clock Buffer" column, the DCM Wizard does not bring the clock signal out to the entity.
This problem is fixed in the latest 5.1i Service Pack, available at:
The first service pack containing the fix is 5.1i Service Pack 2.
An alternate way of working around this problem is to select "LOWSKEWLINES" instead of "Local Routing". To do this, edit the VHDL/Verilog and comment out the following lines:
attribute USELOWSKEWLINES : string;
attribute USELOWSKEWLINES of <signal_name> : signal is "";
Remove the "USELOWSKEWLINES" attribute next to the line started with
output <signal_name> /* take the attribute out */ ;