I have a problem trying to return an action when I'm using a calculated
member to aggregate multiple items.

In the MDX below, I want to see the measure [Deal Count] for all
children of the All level of product for 2 days where 38503 and 38504
are date id's. The MDX is generated by a 3rd party tool.

WITH MEMBER [Bookdate].[yqmd].[All Bookdate].[ Aggregation]
AS ' AGGREGATE( { [Bookdate].[yqmd].[The Date].&[38503],
[Bookdate].[yqmd].[The Date].&[38504] }) ', SOLVE_ORDER = 0

SELECT
NON EMPTY { [Measures].[Deal Count] } ON COLUMNS ,
NON EMPTY { [Product].[All Product].CHILDREN } ON ROWS
FROM
[fxdistribution]
WHERE
( [Bookdate].[yqmd].[All Bookdate].[ Aggregation] )


I then want the user to be able click on a cell to get a drillthrough
via an action that would call a custom web page.

So I have created a cell-level action with the following value:
"http://servername/results.asp?DateIDs=" +
[BookDate].[yqmd].CurrentMember.Properties("key") + "&Product=" +
[Product].CurrentMember.Properties("key")


Now, if I DON'T have the calculated member to aggregate the 2 days for
the filter, and I just have 1 day selected - this MDX works fine - I
get my action working.

But when I DO have the calculated member to aggregate the 2 days for
filtering, I get an error from the 3rd party application when firing
the action:
"Error Occurred during attempt to iterate schema"

I presume this is because I'm using the CurrentMember method, when in
actual fact, I've really got more that one member - i.e. 2 days.

Is there an MDX statement I can use in this action that would list all
of the selected days? (i.e.. something like: [day1],[day2])

OR

Is there another way to do this?

(I have tried native drillthroughs, but have hit other show stopping
limitations of drillthrough to detail against calculated members.)