[R] colClasses = "Date" in read.delim, how to pass date-format?

[Christoph Lehmann]

Hi
I have a huge data-set with one column being of type date.
Of course I can import the data using this column as "factor" and then 
convert it later to dates, using:

sws.bezuege$FaktDat <- dates(as.character(sws.bezuege$FaktDat),
                              format = c(dates = "d.m.y"))


But the conversion requires a huge amount of memory (and time), 
therefore I would like to use colClasses = c("Date"). My question is:
since I have format  = c(dates = "d.m.y"), how can I pass this option to 
read.delim(..., colClasses = c("Date")) ?

thanks for a hint

cheers
christoph