Yes, it works!

Is smb.conf i have:
[global]
......
client code page = 852
encrypt passwords = yes
include = /etc/samba/machine/smb.conf.%m
......

than I have 3 types of smb.conf.%m files for following machnes:

Win95 with cyrillic: smb.conf.w95rus
[global]
client code page = 866
encrypt passwords = no

Win98 with cyrillic: smb.conf.w98rus
[global]
client code page = 866

Win95 with East-European: smb.conf.w95hun
[global]
encrypt passwords = no


Then I just add symlink for each machine which needs settings other
than in default smb.conf file. This way the unencrypted passwords have
to work only for Win95 machines and not for others.

Thank everybody for your help!