Kernel seems to crash in a xen environment and using crossover-office

[Daniel Rindt]

Hello Listmembers,

iam running Fedora 8 into a Xen Environment. My Kernel on the domU is
2.6.21-2950.fc8xen. This domU has 1024M of Ram assigned. When iam
starting the Crossover Installer Wizard and choose Install Internet
Explorer 6 SP1 then the Kernel seems to crash. With the virt-manager i
had taken a Screenshot from the console, he is attached. If iam lowering
the Memory to 512M the Crash comes later in the Setup or using. 
Additionally i found these messages too:
=== 8< ===
4gb seg fixup, process exe (pid 2457), cs:ip 73:0804d5a1
4gb seg fixup, process exe (pid 2457), cs:ip 73:0804d5a1
4gb seg fixup, process exe (pid 2457), cs:ip 73:00aea736
4gb seg fixup, process exe (pid 2457), cs:ip 73:0804d596
4gb seg fixup, process exe (pid 2457), cs:ip 73:00aebcb0
4gb seg fixup, process exe (pid 2457), cs:ip 73:0804d5a1
4gb seg fixup, process exe (pid 2457), cs:ip 73:00aea736
4gb seg fixup, process exe (pid 2457), cs:ip 73:0804d5a1
4gb seg fixup, process exe (pid 2457), cs:ip 73:00c153e7
4gb seg fixup, process exe (pid 2457), cs:ip 73:0804d596
printk: 171 messages suppressed.
=== 8< ===
If iam using some Windows Software with Crossover then i found after 2-4
minutes the following in my dmesg:
=== 8< ===
4gb seg fixup, process wine-pthread (pid 2857), cs:ip 73:741dfb5a
printk: 164944 messages suppressed.
=== 8< ===
the problem can definitly influenced through the memory dimensioning. I
dont know why the machine knows that he had 4G of memory at all.

In hope for answer and suggestions how to avoid/ solve that - many
thanks in advance. Thanks for reading this mail.

-Daniel

P.S.: i had do a xm dump-core, its bzipped now so i can provide it if
someone request it for analyzing.