Table field problem

Dear Experts,

I have defined a date field in my user defined table as a CHAR10 field.

When I made a selection as follows to this table in SE11, with the field I mentioned above:
25.10.2012 - 10.11.2012,

I get an errot that the "lower limit is greater than upper limit".

It is understood why this error comes up ,but due to some restrictions I need to maintain it as a  character field.Do I have any other options to make such a selection to the table.

Please see the attached file.

Thanks
P