Setting parameter range which is accessing values from a dynamic pick list

Hi All,

I have designed a report where in it consists of two parameters date and username.

for this have created one dynamic picklist that consists of date and username.

I need to provide a range for values for "date paramerer"

When i am trying to set the "allow range values" property to "TRUE",it is not allowing me to do so when the parameter status is set to "Dynamic".The same thing works if it is set for "Static"

kindly help me out in this issue.

Regards,

Babu.