I have set up GroupWise Web Access 8.0HP1. This all seemed to be working
well when someone pointed out to me that they were not able to login
using IE (any version).

The web server is Tomcat which is reverse-proxied behind Apache. Apache
connects to Tomcat using mod_jk (this is a SLES 9 box so mod_proxy_ajp is
not a possibility).

There is a mod_rewrite redirection from !^gw\/webacc (i.e. anything not
under /gw/webacc) to the Web Access login page.

As I said this was all working well under Firefox but I found that any
version of IE I tried came up with the "Your login is not current" error.

I managed to resolve this by editing the file /srv/www/tomcat/base/
webapps/gw/webaccess/200901270432/css/gwstyle.css. I changed ...

behavior: url(../css/pngbehavior.htc);

.... to ...

behavior: url('/gw/webaccess/200901270432/css/pngbehavior.htc');

I got to that answer by inspecting the rewrite logs and finding that the
browser was requesting "/css/pngbehavior.htc" for some reason. Hey I
don't know why this seemed necessary but it did fix the issue and I
suppose this might help someone else with a similar configuration. A
similarly configured SLES 10 SP2 box which has mod_proxy_ajp behaves
identically and because mod_proxy_ajp doesn't require anywhere near as
much config as mod_jk it is less likely that I have something mis-
configured on the SLES 10 box and yet the behaviour is the same.

If the rewrites are turned off it all just works by the way, so this is a
particular config that causes this issue.