I'm pretty sure that the document module doesn't currently do that on a user by user basis.
You can of course lock a document module (both view and edit) to single security role though.

If your user count is not very large (like for a small company intranet) you might want to give every user
their own security role and then they could also each have their own document module. 
All of the document modules could reside on the same pane of the same page but since each is set to be viewed by only a single security role, only one module would appear when a given user visited the page.

This wouldn't be practical for a large user base, but it would give you the effect that your looking for.

Hope it Helps,
Peace,
Colt

first of all Thnx 4 replyng ..

actually i m looking for something like Role Assignment Just like  "Item Authorized Documents"  which i found in SnoCovered Website ... here ... http://www.snowcovered.com/snowcovered2/Default.aspx?tabid=166&CatalogItemID=2882&CatalogID=7&MasterCategoryID=16&SubCategoryID=69&pagenumber=0&sortby=

but the problem is its not Open Source but is PAID .. here we can assign Role Permissions for each User .. this is what i m trying to do ..

can anupne of u help me in that ... and also .. i found here in this FORUM only .. this thing .. "Ideas for the module... " http://www.dotnetnuke.com/Community/ForumsDotNetNuke/tabid/795/forumid/19/threadid/3063/scope/posts/Default.aspx

there is a sugession for Document Module ... like this ... "Individual access rights, extend the access right lists to include all items in the list, so that access can be set on document level, the above group level with fallback to the module access definitions. This access will work as a refinement and not overrule any module or page rights."

......... but i couldn't find if the Module containing this feature has been built or Not ... can u tell me where can i find this module or what was its Version...

mine DotNetNuke Version is : 3.0.13 ... so above mentioned feature is exactly what i m looking for !!!

thnx !!! once again ..