WIld card DNS used to work, no more

Apologies in advance for the possible noob question For sometime I've used wildcard DNS, basically making the server * in DNS manager. Now though it doesn't work anymore. I get the following in the log: 30-Apr-2007 22:37:47.374 dns_rdata_fromtext: sub.domain.com.zone:2: near '*.sub.domain.com.': bad name (check-names). I don't kno exactly when this happened, because this particular requirement was not in use for a month or 2. Any ideas? TIA BP