Vista - Exporting partial Event Log as .evt file

My first problem got solved - couldn't get
"Win32_NTEventLogFile.BackupEventLog(path)" to work. Urkec pointed out that
when connecting to a remote computer, WMI methods often can only write to a
local path on that remote computer.

Now I'm trying to figure out how to get a partial ".evt" file export,
instead of exporting the entire log.

For example, the following code exports the entire application log:

Set colLogFiles = objWMIService.ExecQuery _
("Select * from Win32_NTEventLogFile " _
& "Where LogFileName='Application'")
For Each objLogfile in colLogFiles
errBackupLog = objLogFile.BackupEventLog( _
remoteWMIpath & "EventLog.evt")

.. . . but what if I want to retrieve only the last month's worth of entries?

The "Win32_NTLogEvent" class facilitates qualification of each log event by
date. Once a log event is qualified, however, it doesn't appear to me that
there's a straight-forward way to export individually-qualified log events
into a .evt file, such that the end result is formatted the same way it would
have been with the Win32_NTEventLogFile.BackupEventLog class/method.

Is there a simple way to get a partial date range exported as a "standard"
..evt file, without having to manually contruct each exported event? (assuming
that such a manual contruct 's even possible)

Thanks,

David