for 1.8
find in memberlist :
<tr>
<td class="thead" colspan="7">
<div class="float_right">
<a href="memberlist.php?username_match=begins&username={$lang->a}" style="padding: 5px;">{$lang->a}</a>
<a href="memberlist.php?username_match=begins&username={$lang->b}" style="padding: 5px;">{$lang->b}</a>
<a href="memberlist.php?username_match=begins&username={$lang->c}" style="padding: 5px;">{$lang->c}</a>
<a href="memberlist.php?username_match=begins&username={$lang->d}" style="padding: 5px;">{$lang->d}</a>
<a href="memberlist.php?username_match=begins&username={$lang->e}" style="padding: 5px;">{$lang->e}</a>
<a href="memberlist.php?username_match=begins&username={$lang->f}" style="padding: 5px;">{$lang->f}</a>
<a href="memberlist.php?username_match=begins&username={$lang->g}" style="padding: 5px;">{$lang->g}</a>
<a href="memberlist.php?username_match=begins&username={$lang->h}" style="padding: 5px;">{$lang->h}</a>
<a href="memberlist.php?username_match=begins&username={$lang->i}" style="padding: 5px;">{$lang->i}</a>
<a href="memberlist.php?username_match=begins&username={$lang->j}" style="padding: 5px;">{$lang->j}</a>
<a href="memberlist.php?username_match=begins&username={$lang->k}" style="padding: 5px;">{$lang->k}</a>
<a href="memberlist.php?username_match=begins&username={$lang->l}" style="padding: 5px;">{$lang->l}</a>
<a href="memberlist.php?username_match=begins&username={$lang->m}" style="padding: 5px;">{$lang->m}</a>
<a href="memberlist.php?username_match=begins&username={$lang->n}" style="padding: 5px;">{$lang->n}</a>
<a href="memberlist.php?username_match=begins&username={$lang->o}" style="padding: 5px;">{$lang->o}</a>
<a href="memberlist.php?username_match=begins&username={$lang->p}" style="padding: 5px;">{$lang->p}</a>
<a href="memberlist.php?username_match=begins&username={$lang->q}" style="padding: 5px;">{$lang->q}</a>
<a href="memberlist.php?username_match=begins&username={$lang->r}" style="padding: 5px;">{$lang->r}</a>
<a href="memberlist.php?username_match=begins&username={$lang->s}" style="padding: 5px;">{$lang->s}</a>
<a href="memberlist.php?username_match=begins&username={$lang->t}" style="padding: 5px;">{$lang->t}</a>
<a href="memberlist.php?username_match=begins&username={$lang->u}" style="padding: 5px;">{$lang->u}</a>
<a href="memberlist.php?username_match=begins&username={$lang->v}" style="padding: 5px;">{$lang->v}</a>
<a href="memberlist.php?username_match=begins&username={$lang->w}" style="padding: 5px;">{$lang->w}</a>
<a href="memberlist.php?username_match=begins&username={$lang->x}" style="padding: 5px;">{$lang->x}</a>
<a href="memberlist.php?username_match=begins&username={$lang->y}" style="padding: 5px;">{$lang->y}</a>
<a href="memberlist.php?username_match=begins&username={$lang->z}" style="padding: 5px;">{$lang->z}</a>
</div>
<div><strong>{$lang->member_list}</strong></div></td>
</tr>
replace with:
<tr>
<td class="thead" colspan="7">
<div class="float_right">
<a href="memberlist.php?username_match=begins&username={$lang->a}" style="padding: 5px;">{$lang->a}</a>
<a href="memberlist.php?username_match=begins&username={$lang->b}" style="padding: 5px;">{$lang->b}</a>
<a href="memberlist.php?username_match=begins&username={$lang->c}" style="padding: 5px;">{$lang->c}</a>
<a href="memberlist.php?username_match=begins&username={$lang->d}" style="padding: 5px;">{$lang->d}</a>
<a href="memberlist.php?username_match=begins&username={$lang->e}" style="padding: 5px;">{$lang->e}</a>
<a href="memberlist.php?username_match=begins&username={$lang->f}" style="padding: 5px;">{$lang->f}</a>
<a href="memberlist.php?username_match=begins&username={$lang->g}" style="padding: 5px;">{$lang->g}</a>
<a href="memberlist.php?username_match=begins&username={$lang->h}" style="padding: 5px;">{$lang->h}</a>
<a href="memberlist.php?username_match=begins&username={$lang->i}" style="padding: 5px;">{$lang->i}</a>
<a href="memberlist.php?username_match=begins&username={$lang->j}" style="padding: 5px;">{$lang->j}</a>
<a href="memberlist.php?username_match=begins&username={$lang->k}" style="padding: 5px;">{$lang->k}</a>
<a href="memberlist.php?username_match=begins&username={$lang->l}" style="padding: 5px;">{$lang->l}</a>
<a href="memberlist.php?username_match=begins&username={$lang->m}" style="padding: 5px;">{$lang->m}</a>
<a href="memberlist.php?username_match=begins&username={$lang->n}" style="padding: 5px;">{$lang->n}</a>
<a href="memberlist.php?username_match=begins&username={$lang->o}" style="padding: 5px;">{$lang->o}</a>
<a href="memberlist.php?username_match=begins&username={$lang->p}" style="padding: 5px;">{$lang->p}</a>
<a href="memberlist.php?username_match=begins&username={$lang->q}" style="padding: 5px;">{$lang->q}</a>
<a href="memberlist.php?username_match=begins&username={$lang->r}" style="padding: 5px;">{$lang->r}</a>
<a href="memberlist.php?username_match=begins&username={$lang->s}" style="padding: 5px;">{$lang->s}</a>
<a href="memberlist.php?username_match=begins&username={$lang->t}" style="padding: 5px;">{$lang->t}</a>
<a href="memberlist.php?username_match=begins&username={$lang->u}" style="padding: 5px;">{$lang->u}</a>
<a href="memberlist.php?username_match=begins&username={$lang->v}" style="padding: 5px;">{$lang->v}</a>
<a href="memberlist.php?username_match=begins&username={$lang->w}" style="padding: 5px;">{$lang->w}</a>
<a href="memberlist.php?username_match=begins&username={$lang->x}" style="padding: 5px;">{$lang->x}</a>
<a href="memberlist.php?username_match=begins&username={$lang->y}" style="padding: 5px;">{$lang->y}</a>
<a href="memberlist.php?username_match=begins&username={$lang->z}" style="padding: 5px;">{$lang->z}</a>
</div>
</td>
</tr>
<tr>
<td class="thead"><strong>{$lang->member_list}</strong></td>
</tr>
<tr>
<td class="trow1">
{$users}
</td>
</tr>
the other part of the code that is to replace the whole memberlist_user
still works properly. just need to do the edits i posted to get it to work in mybb 1.8 version.