[imp] change date inbox

[Kakooty]

hi guys
how can i change date in inbox, i means Date in mail when i read it.
i changed it when the mail is list in inbox , but i don't know how 
change the top Date in mailbox.


*Date:*  	Wed, 03 Jun 2009 18:51:22 +0430 [06:51:22 PM IRDT]
*From:*  	kakooty at gmail.com 
<http://10.0.0.232/horde/imp/compose.php?to=azarmehr%40daka.ir> Iran, 
Islamic Republic of
*To:*  	kakooty at gmail.com 
<http://10.0.0.232/horde/imp/compose.php?to=azarmehr%40daka.ir>
*Subject:*  	123