XML schema and XSLT validation

[zandoo]

Hi,

I have the following situation. I have 2 namespaces. In the first one i have the element el1 and in the second el2. Both can have as child elements the other one(el1 can nest el2 and viceversa). The problem is that in el1 i must also be able to nest a child(nested) element from el2, such that this would be valid according to these schemas:

<ns1:el1>
<ns2:el2>
<ns1:el1>
<ns2:child-from-el2/>
</ns1:el1>
</ns2:el2>
</ns1:el1>

How can i do this using only 2 xml schemas one for each namespace? 10x.