import namespace1.MyObject;

rule "r"
  when
    namespace2.MyObject( value == 3 )
    MyObject( attr1 == "foo" ) //Here, got a parsing error stating "attr1" is not a field because it looks it up from namespace2.MyObject
  then
    // ...
end

import namespace1.MyObject;

declare MyLocalType
  val: namespace2.MyObject
end

rule "r1"
  when
    MyObject( attr1 == "foo" ) //Here, got a parsing error stating "attr1" is not a field because it looks it up from namespace2.MyObject
  then
    MyLocalType $mlt = new MyLocalType();
    $mlt.setVal( new namespace2.MyObject() );
    insert( $mlt );
end

rule "r2"
  when
    MyObject()
//Here: there is no name conflict but, at execution time, the rule is not activated;
//fully qualifying the fact type solved the issue (meaning activation seems to wait for namespace2.MyObject to fire the rule...)
  then
    // ...
end