(Trinidad) Table column sorting for case-insensitive

[sandeep gururaj]

Hello All,
 
I have a question on Sorting on a column in a table.
 
<tr:column sortProperty="firstname" sortable="true">
 
Currently with the above tag the column is displaying in a CaseSensitive manner 
like Capital letters first and later Smaller case. Is there any tag/way which 
supports for CaseInSensitive sort?
 
Thanks
~Sandeep