RMAN Backup set until time not working

run
{
set until time 'Jul 27 2005 10:00:00';
restore database;
recover database;
alter database open resetlogs;
}

I keep getting the error "a non-numeric character was found where a numeric was expected"

My PROPS$ Table has Mon DD YYYY for the NLS_DATE_FORMAT
My init file has *.nls_date_format='Mon DD YYYY'

What is the correct way to set the date time when using the command
set until time ?

thanks.

Use to_date('Jul 27 2005 10:00:00','MMM DD YYYY HH24:MI:SS')

That worked. I did not know that you could use to_date within rman.