Problems with missing screen updates on recent version

[Alex Bennee]

Hi,

For a while now I've been noticing screen corruption and missing
updates on rxvt. The first thing I noticed was backspace wouldn't
always update the screen so characters wouldn't disappear until
another one was pressed. Even more corruption is noticeable if I
scroll in mutt or execute something with an ncurses interface like the
kernel menuconfig dialogues.

If I move the window from within X then everything corrects itself.
This makes me unsure if it's urxvt itself or one of the X libs in the
background getting confused.

My main machine is a Gentoo one but I'm running with the "vanilla"
flag to disable Gentoo's patches. I've also tried running from a plain
CVS checkout with the same problems. I'm now noticing similar problems
on Ubuntu 10.04 and 11.04 machines running with the latest urxvt
packages.

Can anyone suggest anything I can try to narrow down the potential
causes of the problem?

-- 
Alex, homepage: http://www.bennee.com/~alex/
http://www.half-llama.co.uk