Problem with clipboard

Hi NG,

some how the memo in combinaton with the clipboard shows some strange
behaviour in my application.
In my code I select some text in the memo by draging the mouse. Then I try
to get hold of the selection by:

memo.CopyToClipboard;
aTextStr:=Clipboard.AsText;

but aTextStr is either empty or holds text that I have copied somewhere
elese before (for example code from the unit).
Is there something I have to do, before I make use of the clipboard?

Thanks for hints
Rainer