We have no libvirt-debuginfo package in ALT. Is it one with --enable-debug=yes?
If it is, then here is a result of command
[root@snow tmp]# LIBVIRT_DEBUG=yes virsh create ju >ham 2>&1
Segmentation fault

--------- ham ---------------------------
DEBUG: libvirt.c: virInitialize (register drivers)
DEBUG: libvirt.c: virRegisterDriver (registering Test as driver 0)
DEBUG: libvirt.c: virRegisterNetworkDriver (registering Test as network driver 0)
DEBUG: libvirt.c: virRegisterStorageDriver (registering Test as storage driver 0)
DEBUG: libvirt.c: virRegisterDeviceMonitor (registering Test as device driver 0)
DEBUG: libvirt.c: virRegisterDriver (registering Xen as driver 1)
DEBUG: libvirt.c: virRegisterDriver (registering OPENVZ as driver 2)
DEBUG: libvirt.c: virRegisterDriver (registering remote as driver 3)
DEBUG: libvirt.c: virRegisterNetworkDriver (registering remote as network driver 1)
DEBUG: libvirt.c: virRegisterStorageDriver (registering remote as storage driver 1)
DEBUG: libvirt.c: virRegisterDeviceMonitor (registering remote as device driver 1)
DEBUG: libvirt.c: virConnectOpenAuth (name=(null), auth=0x1e66dc, flags=0)
DEBUG: libvirt.c: do_open (no name, allowing driver auto-select)
DEBUG: libvirt.c: do_open (trying driver 0 (Test) ...)
DEBUG: libvirt.c: do_open (driver 0 Test returned DECLINED)
DEBUG: libvirt.c: do_open (trying driver 1 (Xen) ...)
DEBUG: libvirt.c: do_open (driver 1 Xen returned DECLINED)
DEBUG: libvirt.c: do_open (trying driver 2 (OPENVZ) ...)
DEBUG: util.c: virExec (/usr/sbin/vzctl --help)
DEBUG: libvirt.c: do_open (driver 2 OPENVZ returned SUCCESS)
DEBUG: libvirt.c: do_open (network driver 0 Test returned DECLINED)
DEBUG: remote_internal.c: doRemoteOpen (proceeding with name = openvz:///system)
DEBUG: remote_internal.c: doRemoteOpen (Adding Handler for remote events)
DEBUG: remote_internal.c: doRemoteOpen (virEventAddHandle failed: No addHandleImpl defined. continuing without events.)
DEBUG: libvirt.c: do_open (network driver 1 remote returned SUCCESS)
DEBUG: libvirt.c: do_open (storage driver 0 Test returned DECLINED)
DEBUG: libvirt.c: do_open (storage driver 1 remote returned SUCCESS)
DEBUG: libvirt.c: do_open (node driver 0 Test returned DECLINED)
DEBUG: libvirt.c: do_open (node driver 1 remote returned DECLINED)
DEBUG: libvirt.c: virDomainCreateXML (conn=0x9dc4940, xmlDesc=<domain type="openvz">
    <name>109</name>
    <memory>524288</memory>
    <os>
        <type>exe</type>
    </os>
    <devices>
        <filesystem type="template">
            <source name="altlinux-Charibdis"/>
            <target dir="/"/>
        </filesystem>
        <interface type="bridge">
            <source bridge="mkvebr0"/>
        </interface>
    </devices>
</domain>
, flags=0)
DEBUG: util.c: virRun (/usr/sbin/vzctl --quiet create 109 --ostemplate altlinux-Charibdis)
DEBUG: util.c: virRun (/usr/sbin/vzctl --quiet set 109 --netif_add eth0,52:54:00:0F:80:3A,veth109.0,52:54:00:0F:80:3A,mkvebr0 --save)
DEBUG: util.c: virRun (/usr/sbin/vzctl --quiet start 109)
DEBUG: util.c: virRun (Command stdout: Adding interface veth109.0 to bridge mkvebr0 on CT0 for CT109
)
DEBUG: util.c: virRun (Command stderr: Error: an inet prefix is expected rather than "0".
/usr/sbin/vznetaddbr: line 34: /proc/sys/net/ipv4/conf/veth109.0/proxy_arp: No such file or directory
/usr/sbin/vznetaddbr: line 35: /proc/sys/net/ipv4/conf/veth109.0/forwarding: No such file or directory
)
---------------------------------------------