Strange behavior of a WOForm: values get nullify

Hi list,
I've been trying to isolate the issue but couldn't really find  
something that "make sense"...
Here's what I have:
-a WOForm with some parts which are displayed using WOConditional
-I'm using an EOGenericRecord as the object container, but it is  
instantiated in the java file with the correct Class (for example, I  
can have different Product subentities but using only one textfield  
in the form for the common attributes)

The strange behavior starts with:
-the "get" method will actually correctly loads all the data and it  
will work. But as some products may have a lot of info in them, the  
get method will fail sometimes.
-the "post" method leads to some data being nullify! it is consistent  
all the time. If I "move" the text input, it works in some places and  
not in some others... It seems to be related to some conditional  
around it, but every tag is correctly closed.

I'm using Wonder on this project, I updated it to see if it could be  
a bug in my version but nothing changed.
I wanted to try without wonder, but I just couldn't apparently  
because I'm using ToOne and ToMany relationship on abstract objects.  
So I can't say if it's Wonder related for sure.
But I recall having some unexpected behavior like this one on another  
project (without Wonder).

I really don't know where to track what's happening, I printed every  
call to my object but it appears it is correctly created (with some  
default value) and when I call my "add" method, the object already  
has some nullified values...

Is there anything I should be aware of using conditional in a WOForm?
I don't seem to have such problem in my other projects (but this one  
has quite a lot ToOne and ToMany relationship in it).

Thanks for any help:)

Xavier