There is not enough information in your problem report. We don't know your hardware architecture, or anything about your hardware configuration, or even what release of OpenBSD you are running. Your dmesg would give us all three.
From the output you have shown, it appears that you are not using an xorg.conf file. You may need or want one.
FAQ 11 will give you guidance in properly configuring the X Windows environment for your particular architecture, hardware, and monitor(s).
It also appears that you are using the XKB keyboard mapping subsystem. I'm not familiar with it, but a quick search of the OpenBSD project website found this comment in an upgrade guide showing xorg.conf changes. It looks like a custom xorg.conf may be required:
http://www.openbsd.org/faq/upgrade-old.html#20060131
And on the misc@ mailing list, I found references to xmodmap:
http://marc.info/?l=openbsd-misc&m=121727431924713&w=2
...and along with xmodmap, the setxkbmap utility and xorg.conf once again:
http://marc.info/?l=openbsd-misc&m=121734064926544&w=2
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Personally, I find fvwm a horrid window manager; it is built-in, but that's it only value as far as I'm concerned. (I understand Theo likes it, which is why it's there.)
Along with fvwm, cwm is also built-in.
There are at least 45 different window managers in the ports tree, available as packages. That includes the window managers which are packaged with applications which make them "integrated" GUI environments (KDE/Gnome/XFCE).