Wrong filter from codeunit 46 - GetSelectionFilter

Hi everyone,

I am using standard codeunit 46 SelectionFilterManagement to extract a filter from a group of records:
I created the following custom functions in my page:

GetSelectionFilterForXXX(VAR recXXX : Record XXX) : Text

recRef.GETTABLE(recXXX );
EXIT(GetSelectionFilter(recRef,recXXX .FIELDNO(FieldXXX)));

GetRecordsXXX(VAR codXXX : Code[20]) : Text

lrecXXX.RESET;
lrecXXX.SETRANGE(Code,codXXX );
EXIT(GetSelectionFilterForXXX(lrecXXX));

GetSelectionFilter is a standard function in codeunit 46.

The problem is that the filter is not correct in some cases :
For example:
When lrecXXX is filtered on the records with the following values for FieldXXX: 1000,1010,1040,6020,6120,9140
The filter is supposed to be : 1000|1010|1040|6020|6120|9140
BUT
this is what I get : 1000|1010|1040|6020|6120..9140

Is there something wrong with my code?
Or this is some kind of bug in the codeunit itself? Has someone experienced this before?

Thanks in advance