How to nest lists to other commands defined in a layout?

[Uwe Stöhr]

I have a question regarding layouts:

For modernCV I have the case that an itemize needs to be within another 
command, e.g.
\cvlistitem{Another single item.\begin{itemize}\item Sub-item.\end{itemize}}

So I need to nest the itemize into the \cvlistitem. but how is this done? I can nest an itemize into 
other lists like an enumerate without problems so there must be a way to make it also nestable to 
other commands but I cannot find out how.

thanks and regards
Uwe