Hy men,

i produced a dropdownlist through getting values from miracle fields:

<?php $dvs = new WP_Query(); ?>
<?php $dvs->query('cat=3'); ?>

    <div class="dvs-menu">

        <!-- List -->

        <p>VS</p>

        <select id="dvs-list">
            <?php while($dvs->have_posts()) : $dvs->the_post(); ?>
                <option class="dvs-list" title="dvs-<?php echo get('dvs_year'); ?>" value="<?php echo get('dvs_year'); ?>">
                    <?php echo get('dvs_year'); ?>
                </option>
                <?php endwhile; // End the loop. Whew. ?>
        </select>

    </div>

I've about 20 values inside, but whatever i actually do, only 10 is going to be proven. Is the fact that an issue of Wordpress, MF or even the browser?

I believe you are striking the conventional pagination limit (10 posts per page.) Pagination is on automatically (is sensible for many Loops) but clearly it's a bad choice for your dropdown list.

Try adding the nopaging choice to disable pagination:

<?php $dvs->query('cat=3&nopaging=1'); ?>

See the docs for additional particulars.