Symptoms

When retrieving data of type Decimal from a SharePoint 2010 list and passing it into DataLabels then filtering a List view based on those data labels, the filter does not work. It displays an error instead of the list items that fall between the 2 values (data labels). The same happens when doing it with parameters instead of data labels.
 

Diagnoses

After some investigation it turned out that this is a bug and a TFS item (600235) has been created for this issue.
 

Resolution

A coldfix has been created by LABS and installed in the customer's environment, which resolved the filtering issue on Smartforms.