I worked it out
UPDATE ubbt_POSTS SET POST_BODY=REPLACE(POST_BODY,"icons/wink.gif","icons/default/wink.gif")
UPDATE ubbt_POSTS SET POST_BODY=REPLACE(POST_BODY,"icons/tongue.gif","icons/default/tongue.gif")
UPDATE ubbt_POSTS SET POST_BODY=REPLACE(POST_BODY,"icons/grin.gif","icons/default/grin.gif")
UPDATE ubbt_POSTS SET POST_BODY=REPLACE(POST_BODY,"icons/confused.gif","icons/default/confused.gif")
UPDATE ubbt_POSTS SET POST_BODY=REPLACE(POST_BODY,"icons/shocked.gif","icons/default/shocked.gif")
UPDATE ubbt_POSTS SET POST_BODY=REPLACE(POST_BODY,"icons/smile.gif","icons/default/smile.gif")
UPDATE ubbt_POSTS SET POST_BODY=REPLACE(POST_BODY,"icons/mad.gif","icons/default/mad.gif")
UPDATE ubbt_POSTS SET POST_BODY=REPLACE(POST_BODY,"icons/frown.gif","icons/default/frown.gif")
UPDATE ubbt_POSTS SET POST_BODY=REPLACE(POST_BODY,"images/blank.gif","images/general/default/blank.gif")
