BEx Exception Aggregation Minimum for (calculated key figure) type DATE

Hi folks,

we do have the follwowing problem, probably someone may help us:

- Key figure type DATE, exception aggregation MINIMUM

- BEx Query: Aggreation within the BEx-Query at a hierarchy: Zero-values are transferred as smallest (MIN) values to the top of the hierarchy, but is wrong, as only "real" values should be aggregated

- a calculated keyfigure was created, regarding to the BW-keyfigure and additionally with exception aggregation (aggregate all values except 0), but this setting only fits for amounts or quantities, no dates ...

Does anyboday has had the same problem and may offer a possible solution?

Your help is very appreciated,

Thanks!

Cheers, Heiko