Issue while renaming attachment in mail adapter in PI 7.3.1 single stack

Hi Exparts,

My requirement is to attach PI message payload in receiver mail after renameing it and converting to txt. I have followed the link

http://wiki.sdn.sap.com/wiki/display/ESOAInfrastructure/Dynamic%20Email%20Attachment%20name%20for%20Received%20Mails%20with%20ASMA%20and%20without%20using%20mail%20package

As per the link additional parameter OMail.AddContentDisposition= false,set in advanced tab will prevent the adapter to add content-disposition automatically so that the value of content-disposition will be taken from PI message header. But renaming of attachment is not occuring. Does PI 7.3.1 support OMail.AddContentDisposition= false parameter? Any help regarding the issue is highly appriciated.