MySQL Error

[Ntenze]

Any help would be appreciated.

Invalid SQL: 
		SELECT
			post.*, post.username AS postusername, post.ipaddress AS ip,
			NOT ISNULL(deletionlog.primaryid) AS isdeleted, i.userid AS installed,
			user.*, userfield.*
			, '' AS field9
		FROM vb3_post AS post
		LEFT JOIN vb3_user AS user ON(user.userid = post.userid)
		LEFT JOIN vb3_userfield AS userfield ON(userfield.userid = user.userid)
		LEFT JOIN vb3_deletionlog AS deletionlog ON(post.postid = deletionlog.primaryid AND type = 'post')
		LEFT JOIN vb3_hacks_install AS i ON(i.threadid=2005 AND post.userid=i.userid)
		WHERE threadid = 2005 AND post.visible = 1
		ORDER BY postid
	
mysql error: Column: 'threadid' in where clause is ambiguous

mysql error number: 1052

Thanks Ntenze