I was struggling with ordering Months in my Calendar Dimension. I wanted to show month names in my graphs and prompts and I wanted them to appear in temporal order (e.g. Jan-Feb-...-Dec). I could not use the Sort option beause it would sort values in alphabetical order.
Since in my dimension I have an attribute with the month number, it would have been great using it for sorting month names. Luckily OBIEE lets you do so, by selecting the column you need to sort in the Logical Layer and applying the Sort Order based on another column.