i think it looks better like this

account.install.php

added tab

[code]
$items['account/preference'] = array(
'name'=>'Preference',
'type'=>'tab',
'parent'=>'account'
);
[/code]

account.php

added 2 functions

[code]
function preference() {
global $client,$timezone;
$timezones = array(
array('value'=>-12,'flag'=>'(GMT -12:00) Eniwetok, Kwajalein'),
array('value'=>-11,'flag'=>'(GMT -11:00) Midway Island, Samoa'),
array('value'=>-10,'flag'=>'(GMT -10:00) Hawaii'),
array('value'=>-9,'flag'=>'(GMT -9:00) Alaska'),
array('value'=>-8,'flag'=>'(GMT -8:00) Pacific Time (US & Canada)'),
array('value'=>-7,'flag'=>'(GMT -7:00) Mountain Time (US & Canada)'),
array('value'=>-6,'flag'=>'(GMT -6:00) Central Time (US & Canada), Mexico City'),
array('value'=>-5,'flag'=>'(GMT -5:00) Eastern Time (US & Canada), Bogota, Lima'),
array('value'=>-4,'flag'=>'(GMT -4:00) Atlantic Time (Canada), Caracas, La Paz'),
array('value'=>-3.5,'flag'=>'(GMT -3:30) Newfoundland'),
array('value'=>-3,'flag'=>'(GMT -3:00) Brazil, Buenos Aires, Georgetown'),
array('value'=>-2,'flag'=>'(GMT -2:00) Mid-Atlantic'),
array('value'=>-1,'flag'=>'(GMT -1:00 hour) Azores, Cape Verde Islands'),
array('value'=>0,'flag'=>'(GMT) Western Europe Time, London, Lisbon, Casablanca'),
array('value'=>1,'flag'=>'(GMT +1:00 hour) Brussels, Copenhagen, Madrid, Paris'),
array('value'=>2,'flag'=>'(GMT +2:00) Kaliningrad, South Africa'),
array('value'=>3,'flag'=>'(GMT +3:00) Baghdad, Riyadh, Moscow, St. Petersburg'),
array('value'=>3.5,'flag'=>'(GMT +3:30) Tehran'),
array('value'=>4,'flag'=>'(GMT +4:00) Abu Dhabi, Muscat, Baku, Tbilisi'),
array('value'=>4.5,'flag'=>'(GMT +4:30) Kabul'),
array('value'=>5,'flag'=>'(GMT +5:00) Ekaterinburg, Islamabad, Karachi, Tashkent'),
array('value'=>5.5,'flag'=>'(GMT +5:30) Bombay, Calcutta, Madras, New Delhi'),
array('value'=>5.75,'flag'=>'(GMT +5:45) Kathmandu'),
array('value'=>6,'flag'=>'(GMT +6:00) Almaty, Dhaka, Colombo'),
array('value'=>7,'flag'=>'(GMT +7:00) Bangkok, Hanoi, Jakarta'),
array('value'=>8,'flag'=>'(GMT +8:00) Beijing, Perth, Singapore, Hong Kong'),
array('value'=>9,'flag'=>'(GMT +9:00) Tokyo, Seoul, Osaka, Sapporo, Yakutsk'),
array('value'=>9.5,'flag'=>'(GMT +9:30) Adelaide, Darwin'),
array('value'=>10,'flag'=>'(GMT +10:00) Eastern Australia, Guam, Vladivostok'),
array('value'=>11,'flag'=>'(GMT +11:00) Magadan, Solomon Islands, New Caledonia'),
array('value'=>12,'flag'=>'(GMT +12:00) Auckland, Wellington, Fiji, Kamchatka')
);

c('
<form action="'.url('account/preferencepost').'" method="post">
'.label(t('Timezone')).'
<select name="new_timezone">');
    foreach($timezones as $arr) {
        if ($client['timezone'] == $arr['value']) {
            $arr['selected'] = 'selected';
        }
        c('<option value="'.$arr['value'].'" '.$arr['selected'].'>'.$arr['flag'].'</option>');
    }
    c('</select>
    <p><input type="submit" value="'.t('Save changes').'" /></p>
    </form>');
}

function preferencepost() {
global $client, $timezone;
setcookie('timezone', $_POST['new_timezone'], time()+360024365,'/');
redirect('account',1);
}
[/code]

these are the functions from the preference module with small changes

dashboard.php

function my_account

removed

[code]
<li>'.url('preference',t('Preference')).'</li>
[/code]