Dynamically generating session calculated members in code with Analysis Services 2008

One problem I come across from time to time is the need to be able to group members on a dimension into buckets, for example if you have a Customer dimension you may want to group your Customers together by age group and run a query that shows sales for the 0-9 age group, the 10-19 age group and so on. If you know what buckets you want then you can simply build this into your dimension in advance by creating another attribute; but what if your users want to be able to change the definition of the buckets themselves from query to query - perhaps they wanted to 5 year age groups rather than 10? I described a bit of a hack you could use on AS2K to do this a while ago, but it doesn't work any more on AS2005 or AS2008 because it uses the unsupported CreatePropertySet function and in any case it was pretty nasty; but the only alternative is to be able to have your client tool dynamically create large numbers of calculated members (one for each bucket) with the appropriate definition and then use these calculated members in your query.