You can create the table in phpMyAdmin

CREATE TABLE `profile_comments` (
`id` int(11) NOT NULL auto_increment,
`uid` int(11) NOT NULL default '0',
`posted_by` int(11) NOT NULL,
`comment` text NOT NULL,
`ip` varchar(255) NOT NULL default '',
`date` datetime NOT NULL default '0000-00-00 00:00:00',
PRIMARY KEY (`id`),
KEY `uid` (`uid`)
);


Are you doing upgrade or new installation ?