### begin_: file metadata
    ### desc : comment out cfmail tags in a coldfusion file

### begin_: init perl
    use strict;
    use warnings;
    my  $sTest  = join '',<DATA>;   ###

### begin_: do the replacement
    $sTest  =~
        s{(<\s*cfmail[^>]*>.*?\s*/\s*cfmail\s*>)}
        {<!---\n$1\n--->}gs;
    print $sTest;

__DATA__
<cfparam name="foo" value="fee" />

<cfmail to="#to_address#">
 yadda yadda yadda
</cfmail>

<cfoutput>
the following cfmail tag is messy, but still
valid cold-fusion CFML
</cfoutput>

<
 cfmail to="#to_address#"
>
 yadda yadda yadda
</    cfmail   >

##</code><code>##

<cfparam name="foo" value="fee" />

<!---
<cfmail to="#to_address#">
 yadda yadda yadda
</cfmail>
--->

<cfoutput>
the following cfmail tag is messy, but still
valid cold-fusion
</cfoutput>

<!---
<
 cfmail to="#to_address#"
>
 yadda yadda yadda
</    cfmail   >
--->