complex pagination again

Hello,
This is me again with a pagination trouble:
I want the first page of each chapter to fullfill these conditions:
    a) have a margin-top of a certain value(let's say "80mm")
    b) still be part of  the pagination syle i mentioned in my last 
post( page number left-justified for left pages and right-justified for 
right pages)
Right now, i can get any get either of a) or b) not both
This a portion of my code:

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<fo:page-sequence-master master-name="sequence-texte">
    <fo:repeatable-page-master-alternatives>
    <fo:conditional-page-master-reference page-position="first" 
master-reference="first-page"/>
        <fo:conditional-page-master-reference 
master-reference="texte-left" odd-or-even="odd"/>
        <fo:conditional-page-master-reference 
master-reference="texte-right" odd-or-even="even"/>
    </fo:repeatable-page-master-alternatives>
</fo:page-sequence-master>

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I need help!