The Bat! provides the macro to automatically find all occurrences of the pattern defined as the regular ex * pression ("regexp") and replace it with the specified "new_text" in the "text" searched. A fourth argument n, which is the number of the matched subpattern, may be optionally supplied. As the "text" to be searched, the result of another macro can be used (for example,% OText). The syntax of this macro is following:
Given macro returns the sender address with modified domain name. I use %OFromAddr macro here instead of %FromAddr because you want probably analyse incoming mail.