Hi All! i'm trying to use regular expression that is a value of AVP. for example: $avp(s:regexp) = '^([1-9][0-9]{6})'; $avp(s:value) = '8881\1'; subst_user('/$avp(s:regexp)/$avp(s:value)/'); and it doesn't work. meanwhile this works properly: subst_user('/^([0-9]{7})/888\1/'); Does anybody know how can i resolve this question? Best regards, Savolainen Dmitri