I had the same problem and fixed it by hard coding the height and width. In the catalog/admin directory edit the file 'information_form.php' around line 94 and replace the <td class="main" width="100%"> </td> tags as follows:
<td class="main" width="100%"><?php
if (DESCRIPTION_EDITOR == 'true' ) {
tep_draw_fckeditor('information_description[' . $languages[$i]['id'] . ']', (($languages[$i]['id'] == $languages_id) ? stripslashes
($edit[information_description]) : tep_get_information_entry($information_id, $languages[$i]['id'], 'information_description')), '800', 300);
} else {
echo tep_draw_textarea_field('information_description[' . $languages[$i]['id'] . ']', '', '100', '20', (($languages[$i]['id'] == $languages_id) ? stripslashes($edit[information_description]) : tep_get_information_entry($information_id, $languages[$i]['id'], 'information_description')));
}
?>
</td>
Hope that helps!
Sb
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