In IC 6.1, Monte Carlo analysis has been moved to ADE XL. So you need to create a ADE XL view. Here is a brief set of instructions on how to do this for your existing ADE state setup. For for more complete set of instructions you can refer to the "ADE XL Users Guide".
From your Virtuoso schematic editor window,: select "Launch->ADE XL". Once the ADE XL window opens you can go to the "Data View" assistant panel and select "Click to Add Test" under "Tests".You will be asked to specify a the design to be used. Afterwards, the "Test Editor" window will appear. The Test Editor window is essentially the same as the ADE window that you are familiar with. From the Test Editor you can load your saved ADE states by selecting "Session->Load State". You can now close the Test Editor window and return to the main ADE XL window. You are now ready to simulate.
By default, ADE XL will be configured to run single point simulations. To enable Monte Carlo analysis, you will need to change the run mode: Look for the field in the top right corner of the ADE XL "Single Run, Sweeps and Corners". Change this field to "Monte Carlo Sampling". Select the "Simulation OPtions" button beside this field to adjust the number of points, etc. Finally,, select the run button to lbegin the Monte Carlo.