[TYPO3] tt_news: how to give multiple values in 'General Record Storage page' field?

[Bing Du]

Hi,

Typo3 V4.0.4
tt_news 2.4.0

We're running multiple sites on one typo3 installation (one page tree, one
mysql database).  For each site, there is a sysFolder that has the news
categories and also news articles of that site.

 news sysfolder for site1
 news sysfolder for site2
 news sysfolder for site3
 ...
 ...

Now I want to show a CATMENU of 'news sysfolder for site1' and 'news
sysfolder for site2' on a page.

If I understand correctly how tt_news works, I should enable the
installation option 'use general record storage' of tt_news in extension
manager.  And then in the page properties of the page on which I want to
show the CATMENU, specify in the field 'General Record Storage page' where
the desired news categories reside.  But 'General Record Storage page' is
a  single-valued field.  How can I create the CATMENU out of two general
record storage pages?

Any ideas?

Thanks much in advance,

Bing