[TYPO3-english] Typoscript: compare date

[Leo Führinger]

Hello,
I am using a pre-filled dropdown-menu in powermail. My aim is to show all
seminars (tx_seminars) that are in sysfolder with PID 33.
The Name is composed of the begin_date and seminar-title.

Now, I would like to display only the records that are in the future.
begin_date >= date:U

Unfortunately this isn't working....
Do you have any ideas or suggestions about why this isn't working and how i
could manage to overcome the problem?

This is the TS-setup:
lib.veranstaltungen = COA
lib.veranstaltungen.10 = TEXT
lib.veranstaltungen.10.value = bitte wählen...| [\n]
lib.veranstaltungen.20 = CONTENT
lib.veranstaltungen.20 {
  table = tx_seminars_seminars
  select {
    # nur Datensätze im Ordner 33 anzeigen
    pidInList = 33
    # nur Datensätze anzeigen, die aktueller als heute (date:U) sind.
    #TODO
    #where = begin_date >= date
    andWhere {
      #begin_date > date:U
      #wrap = date >=|
    }
    orderBy = begin_date
  }

  renderObj = COA
  renderObj {
    #1 = TEXT
    #1.data = date:U

    5 = TEXT
    5.field = begin_date
    5.strftime = %d.%m.%Y

    10 = TEXT
    10.field = title
    10.noTrimWrap = | - | |

    stdWrap.wrap = |[\n]
  }
}

Here's an example:
http://www.bergzeit-ettlingen.de/veranstaltungen/anmeldung/s
eite-nach-anmeldung.html

Thanks for your help,
Leo