Does anybody know how to set digit grouping in a SELECT statement?

I run the following select statement:
SELECT node_name,sum(PHYSICAL_MB) as MB FROM OCCUPANCY WHERE
stgpool_name='TAPEPOOL' GROUP BY node_name ORDER BY MB DESC

The output returned looks like this:

NODE_NAME                                             MB
------------------     ---------------------------------
SERVER01                                       255441.88
SERVER02                                       123943.06
SERVER03                                        55192.80
.
.
.
.


However, I would like to have a delimiter for each three digits so the
output looks something like this instead:

NODE_NAME                                             MB
------------------     ---------------------------------
SERVER01                                      255,441.88
SERVER02                                      123,943.06
SERVER03                                       55,192.80
.
.
.
.


Can it be done?


Regards,

Christian