sure is possible
<!-- thumbnail first gallery -->
<a href="01.jpg" rel="gallery"><img src="01thumb.jpg" title"whatever" /
></a>
<!-- thumbnail second gallery -->
<a href="a.jpg" rel="gallery_2"><img src="a_thumb.jpg"
title"whatever" /></a>
<div style="display:none;">
<!-- first gallery-->
<a href="02.jpg" rel="gallery"></a>
<a href="03.jpg" rel="gallery"></a>
<a href="04.jpg" rel="gallery"></a>
.
.
etc
<!-- second gallery-->
<a href="b.jpg" rel="gallery_2"></a>
<a href="c.jpg" rel="gallery_2"></a>
<a href="d.jpg" rel="gallery_2"></a>
.
.
etc
</div>