VB. Net and serializing objects

If you could spare a minut of your time, i could need some help regarding the article below:

http://msdn.microsoft.com/library/en-us/dnnetcomp/html/compactfxsdebeta1.asp?frame=true&_r=1

I have success in recieving a Tradecoll (Collection af trade) at the client.

But how do I get the client to pass a tradecoll (array of trades) into the webservice from the Client, and later on into the desktop mashine sqldatabase. I can not figure out how to write this code, I have tried a lot, but without any luck.

I know it have some thing to do with serializing the tradecoll at the right way !
I hope you can give an answer, and thanks A lot

Regards
der