The generated attributes HTML already includes an ID with each pulldown menu's markup:
PHP Code:
$options_menu[] = zen_draw_pull_down_menu('id[' . $products_options_names->fields['products_options_id'] . ']', $products_options_array, $selected_attribute, 'id="' . 'attrib-' . $products_options_names->fields['products_options_id'] . '"') . "\n";
I must be misreading what you meant to say about what was missing.
Aren't you causing multiple identical ID tags to be output to your page, thus breaking validation?
ie:
Code:
<div class="wrapperAttribsOptions" id="attrib-2">
<h4 class="optionName back"><label class="attribsSelect" for="attrib-2">Size</label></h4>
<div class="back">
<select name="id[2]" id="attrib-2">
<option value="19">X-Small</option>
<option value="21">Small</option>
<option value="18" selected="selected">Medium</option>
<option value="20">Large</option>
</select>