Ubuntu 9.04 guest extremely slow kernel compiling

[rpra]

Host is Windows 7 Ultimate 32 bit Ubuntu 9.04 server edition 32 bit installed without any problem, but when I try to compile:

root@router:~# cd /usr/src/linux
root@router:/usr/src/linux# make-kpkg clean
exec make -f /usr/share/kernel-package/ruleset/minimal.mk clean

Last command hangs, I was waiting for about 30 minutes. On real machines this operation takes less than a minute.

While watching top I can see <defunc> processes gcc, make etc. I can't figure out what is the problem.