Mail check xfce panel item

[Tuukka]

Hello to everyone

I have noticed a slight bug in xfce panel. Menu popup doesn't work if
the shown item is a "mail check"-item. I use the default xfce4rc
where the fourth menu from left contains dillo, gftp and mozilla with
pine set as "mail check"-item. As it is this menu doesn't work.

If it is desired that "mail check"-item doesn't have menu then the
default xfce4rc should be edited to reflect this.

-Tuukka Mäkinen