What steps will reproduce the problem?
1. call MyActiveRecord->withText()->withUser()->find(...) (important: at 
least 2 times withXXX()) with a criteria such that the result is NULL (no 
record found)
2. then use another ActiveRecord like this: MyOtherActiveRecord-
>withSomething()->find(...) (important: at least one withXXX())

What is the expected output? What do you see instead?
It will complain about properties not found in MyOtherActiveRecord (unless 
MyOtherActiveRecord doesn't have the same properties as MyActiveRecord).

Version:
prado 3.1.5a

Fix proposition:
The problem lies in class TActiveRecordRelation, method __call: If the 
result of find() is null, the static variable $stack still references some 
stuff related to the ActiveRecord. If you then use another ActiveRecord 
these references are confusing it. Therefore I propose to clear the 
"stack" if the result is null. Like this:

modify method TActiveRecordRelation::__call() as follows:
[code]
if ($validArray || ...) {
	...
}
elseif($results instanceof TActiveRecordRelation) 
	$stack[] = $this; //call it later
elseif ($results === null) {
	$stack = array();
}
[/code]