livebinding image to blob

i assigned a Timage.Bitmap to a aureliusdataset.blobfield. Having an image saved in the DB it is correctly displayed. But if i assign a new image to the bitmap-property of the TImage it is not saved to the db.
What can i do?
I allready tried to load the image in a TMemoryStream and loadfromstream it to the blobfield of the datasets current object. But even this did not work!

OK i got it by using TFile as described in
But anyway is there a posibiltiy to use livebindings for this???

Have you seen this discussion?