I have never seen this syntax, and a quick look through the DBI book doesn't yield any likening to this syntax.
You really should just fetch the rows (individually or all at once) and then loop through and print them out if you're wantin to output the contents of a select statement. P.S. - I have been known to be wrong many many times.
edit: popped open my sql server docs and found that it's a T-SQL function. My understanding has been that you can use T-SQL via ODBC, but I don't quite think you need to use it here. This may be one function that doesn't work within DBI::ODBC due to what state the cursor needs to be in for the T-SQL command to work.
P.P.S. Again ... I have been known to be very wrong.