windows not redrawing

[Brian <dol-sen telus net>]

We are developing a python gtk app with several windows.  We are getting
intermittent redraw failures in that the windows just have blank
silhouettes.  All icons, menu items, etc are click-able, menus and
popups (even gtk stock ones) just come up grey silhouettes We are able
to get portions to redraw by clicking where something should be to cause
a change, moving scollbars, etc..

Basic program description:
Our Main window is a package browser, etc., adds jobs to the terminal's
queue.
Our terminal window starts hidden, shows when it receives it's first
job, spawns subprocesses from the queue to install packages, has several
notebook tabs, a small menu selection, reads the output from the
subprocesses and puts it in one notebook tab, upon completion sends a
callback signal to the main window in order for it to update itself.  We
also process the output to copy certain messages to other tabs for
easier reference (warnings, extra instructions).

The only thing we have been able to determine is it happens only after a
process is finished, but not consistently.   We also experience some
intermittent scroll problems in the terminal's process textview.   

Is there something we are missing that could cause this intermittent
behaviour?    Any ideas what to look for?
-- 
Brian <dol-sen telus net>