PDO include table name prefixes in FETCH_ASSOC

Many of my MySQL tables have columns with the same name.  I want to have 
PDO include table names in named result sets.  For example:

   $sth = $dbh->prepare("SELECT * FROM table0, table1");
   $result = $sth->fetchAll(PDO::FETCH_ASSOC);


I want $result to be organized like:

   echo $result["table0.column0"];
   echo $result["table0.column1"];
   echo $result["table1.column0"];
   echo $result["table1.column1"];


Or, alternatively:

   echo $result["table0"]["column0"];
   echo $result["table0"]["column1"];
   echo $result["table1"]["column0"];
   echo $result["table1"]["column1"];


Any ideas?  Thanks!


--Aaron