Problem with filters with nameexpression

Hi,
I have a big problem concerning NameExpression tag.
I tried to change current formatting of Month column in such manner:
<Level caption="Discrepancy arrival date Month" column="MONTH" hideMemberIf="Never" levelType="TimeMonths" name="Month" ordinalColumn="MONTH" type="Numeric" uniqueMembers="false">
<Annotations>
<Annotation name="AnalyzerDateFormat">[yyyy].[M]</Annotation>
</Annotations>
<NameExpression>
<SQL dialect="oracle">TIME.YEARMONTH</SQL>
</NameExpression>
</Level>
And during browsing of the cube in Analyzer tool everything seems to works fine but it isn't, because now if I try to define on such column a filter with option Current Discrepancy arrival date Month checked i get no data. Now if i delete the NameExpression:
<Level caption="Discrepancy arrival date Month" column="MONTH" hideMemberIf="Never" levelType="TimeMonths" name="Month" ordinalColumn="MONTH" type="Numeric" uniqueMembers="false">
<Annotations>
<Annotation name="AnalyzerDateFormat">[yyyy].[M]</Annotation>
</Annotations>
</Level>
And try again to add a filter with aforementioned option checked then I get some results. It seems that something went wrong because in pentaho logs storing executed queries in where condition instead of value for a certain month I got 1=0.

Please help ASAP.
P.S: I'm using Pentaho version: 4.8