Techniques for Recognizing DML Effects?

At last glance, some of the current trigger-based asyncronous master-slave
replication tools (dbmirror, rserv, erserver) do not support DML statement
replication. If certain DML statements are executed on a master, say
CREATE TABLE or DROP COLUMN, adjustments must be made on the slave as well.
A warning of such an occurrence would be useful for an administrator.

Is there a simple means of recognizing when a DML statement has occurred on
a cluster strictly by querying system tables? Other ideas as to how to
most easily recognize DML changes in an automated fashion, short of
continually grepping server logs?

Ed