UTF-8에서 작업했습니다.

////////////////

<?
echo "<table cellpadding='0' cellspacing='5'>";
$ca_menu = explode("|",$board[bo_category_list]);
for ($c=0, $cnt=count($ca_menu)/2; $c<$cnt; $c++) { //전체카테고리수를 2로 나눈값만큼 배열
$even_c = $c * 2 ;        // $c[0], $c[2], $c[4], .........
$odd_c = $even_c + 1 ; // $c[1], $c[3], $c[5], .........
echo "<tr>";
echo "<td width='50%'>";
echo "<a href='{$g4['bbs_path']}/board.php?bo_table=$bo_table&sca=".urlencode($ca_menu[$even_c])."'>$ca_menu[$even_c]</a></td>";
echo "<td width='50%'>";
echo "<a href='{$g4['bbs_path']}/board.php?bo_table=$bo_table&sca=".urlencode($ca_menu[$odd_c])."'>$ca_menu[$odd_c]</a></td>";
}
echo "</tr></table>";
?>