Have you read the yellow asterisk message about bluetooth at top of discussions board... you can do it with a thrid party app such as Bluetooth File Transfer from the android market.
http://gadgets.apnafundaz.com/2010/08/how-to-transfer-files-using-bluetooth-on-xperia-x10-mini-and-m...
The above is a how to guide, I believe there is also a guide in the SE blog about it because it is such a common question. It can be done and once you have the knack its straightforward. Have a search on this site too because it is a question that has been asked many times.
