SELECT IN query using ormExecuteQuery()

I'm trying to do a SELECT IN query using ormExecuteQuery().  Following is the code I have:

Categories = ormExecuteQuery("from Category where Id IN (?)",[CategoryList]);

It only works when there is 1 value in the CategoryList.  i.e. This works:

Categories = ormExecuteQuery("from Category where Id IN (?)",[9]);

This DOES NOT work:

Categories = ormExecuteQuery("from Category where Id IN (?)",[8,9,10]);

Help would be greatly appreciated.