Got error 'repetition-operator operand invalid' from regexp<br><br>select count(gc_ads.n)  from gc_ads,gc_index where (    (t1<=1752159953 OR t1=0) AND (t2>=1752159953 OR t2=0) AND status = 'enabled' AND x_paypal_disabled = '0' ) and ((gc_index.all_text REGEXP '+21'))  AND gc_ads.n = gc_index.n