hi, thank you for ur reply.
Yes i can do customized URL (and i might if i dunn find better way), but the thing is that i have too many url to customize...
Cz my site has 4 languages available and sharing content through my multisites might become a common task for my multiple admins... 
anyway, i tried to make a sh404sef ext plugin (as usual to set rewrite rules) but if i use this 'com_multisitescontent.php' extension, the sh404sef does its job but it also prevents com_multisitescontent's url rewritting process (which i cannot find?!) 
So with this extension i made i can remove 'site_id' but no other vars from url! ...
here is what i put in 'com_multisitescontent.php':
| Code: | 
| 
 //shRemoveFromGETVarsList('option');
 shRemoveFromGETVarsList('lang');
 /*  if (!empty($view))
 shRemoveFromGETVarsList('view');
 if (!empty($layout))
 shRemoveFromGETVarsList('layout');
 if (!empty($Itemid))
 shRemoveFromGETVarsList('Itemid');
 if (!empty($id))
 shRemoveFromGETVarsList('id');*/
 if (!empty($limit))
 shRemoveFromGETVarsList('limit');
 if (isset($limitstart))
 shRemoveFromGETVarsList('limitstart');
 if (isset($site_id))
 shRemoveFromGETVarsList('site_id');
 
 | 
what is commented is the vars needed for the process to work fine.
perhaps if i find the rewrite process of multisitescontent i can paste the code in this sh404sef ext i made...
what do u think of it?
i'm getting workin on it and will post my solution if i work some out, please let me know if u have any better idea than mine.
thank u for ya time.