Remove Span from button

[ezramod]

hello , im new in this CMS and i have some problem when i try to edit some button for exemple for review button in product_info.php page i have this code for review button:

  <?php echo tep_draw_button(IMAGE_BUTTON_REVIEWS . (($reviews['count'] > 0) ? ' (' . $reviews['count'] . ')' : ''), 'comment', tep_href_link(FILENAME_PRODUCT_REVIEWS, tep_get_all_get_params())); ?>

and in website appear this:

<span class="">
<a id="tdb5" href="#" class="ui-button ui-widget ui-state-default ui-corner-all ui-button-text-icon-primary ui-priority-secondary ui-state-focus ui-state-hover" role="button">
<span class="ui-button-icon-primary ui-icon ui-icon-comment"/>
<span class="ui-button-text">Comentarii</span>

if read this code you view unnecessary <span> code for exemaple i don't need this span <span class=""> and <span class="ui-button-icon-primary ui-icon ui-icon-comment"/> because i want to create a sample button, in what file is create this button with all this unecessary span? where need to modfy for remove this span?

Sorry for my bad english.