XPages FileUpload control multiple files

Question

In my XPages application I want to upload multiple files. I've added the attribute "multiple" to the control. Now I can select several files, but only the last selected file is saved.

<xp:fileUpload id="fileUpload2" value="#{document1.rtWeb}">
    <xp:this.attrs>
        <xp:attr name="multiple" value="true" />
    </xp:this.attrs>
</xp:fileUpload>

What am I doing wrong? Is that the correct way or am I missing the point?