breaking hierarchy by calculated set

[rellaize]

Hi,
I've got seemingly simple situation - got calculated set eg. periodsToDate(Year, Time->?pPar?). Then when I'm trying to put it into crosstab rows together Quarter level, I get either error OP-ERR-0049 Unable to support a grouping that breaks the hierarchical order of the query items within it. or Quarter has all members in crosstab eg.:
...
2006Q1
2006Q2 April
2006Q2 May
2006Q2 June
2006Q3
...

In list it works fine. I've been trying to overwrite dimension info, assign calculated set to different hierarchy, hierarchize function, with no result..

Attached example on go sales.

Appreciate any help.

rella